1. Introducción

Este documento enumera los requisitos que se deben cumplir para que los dispositivos sean compatibles con Android 6.0.

El uso de “DEBE”, “NO DEBE”, “REQUERIDO”, “DEBE”, “NO DEBE”, “DEBE”, “NO DEBE”, “RECOMENDADO”, “PUEDE” y “OPCIONAL” es según el IETF. estándar definido en RFC2119 [ Recursos, 1 ].

Tal como se utiliza en este documento, un "implementador de dispositivos" o "implementador" es una persona u organización que desarrolla una solución de hardware/software que ejecuta Android 6.0. Una “implementación de dispositivo” o “implementación” es la solución de hardware/software así desarrollada.

Para ser considerada compatible con Android 6.0, las implementaciones de dispositivos DEBEN cumplir con los requisitos presentados en esta Definición de compatibilidad, incluido cualquier documento incorporado mediante referencia.

Cuando esta definición o las pruebas de software descritas en la sección 10 no dicen nada, son ambiguas o están incompletas, es responsabilidad del implementador del dispositivo garantizar la compatibilidad con las implementaciones existentes.

Por esta razón, el Proyecto de código abierto de Android [ Recursos, 2 ] es tanto la referencia como la implementación preferida de Android. Se RECOMIENDA ENCARECIDAMENTE a los implementadores de dispositivos que basen sus implementaciones en la mayor medida posible en el código fuente "ascendente" disponible en el Proyecto de código abierto de Android. Si bien hipotéticamente algunos componentes pueden reemplazarse con implementaciones alternativas, se RECOMIENDA ENCARECIDAMENTE no seguir esta práctica, ya que pasar las pruebas de software será sustancialmente más difícil. Es responsabilidad del implementador garantizar la compatibilidad total del comportamiento con la implementación estándar de Android, incluido y más allá del Compatibility Test Suite. Finalmente, tenga en cuenta que este documento prohíbe explícitamente ciertas sustituciones y modificaciones de componentes.

Muchos de los recursos enumerados en la sección 14 se derivan directa o indirectamente del SDK de Android y serán funcionalmente idénticos a la información contenida en la documentación de ese SDK. En cualquier caso en el que esta Definición de compatibilidad o el Conjunto de pruebas de compatibilidad no estén de acuerdo con la documentación del SDK, la documentación del SDK se considera autorizada. Cualquier detalle técnico proporcionado en las referencias incluidas en la sección 14 se considera por inclusión parte de esta Definición de Compatibilidad.

2. Tipos de dispositivos

Si bien el Proyecto de código abierto de Android se ha utilizado en la implementación de una variedad de tipos de dispositivos y factores de forma, muchos aspectos de la arquitectura y los requisitos de compatibilidad se optimizaron para dispositivos portátiles. A partir de Android 5.0, el Proyecto de código abierto de Android pretende abarcar una variedad más amplia de tipos de dispositivos, como se describe en esta sección.

Dispositivo portátil Android se refiere a una implementación de dispositivo Android que normalmente se usa sosteniéndolo en la mano, como reproductores de mp3, teléfonos y tabletas. Implementaciones de dispositivos portátiles Android:

• DEBE tener una pantalla táctil integrada en el dispositivo.
• DEBE tener una fuente de energía que proporcione movilidad, como una batería.

Dispositivo Android Television se refiere a una implementación de dispositivo Android que es una interfaz de entretenimiento para consumir medios digitales, películas, juegos, aplicaciones y/o TV en vivo para usuarios sentados a unos diez pies de distancia (una “interfaz de usuario de 10 pies” o “inclinada hacia atrás”). ”). Dispositivos de televisión Android:

• DEBE tener una pantalla integrada O incluir un puerto de salida de video, como VGA, HDMI o un puerto inalámbrico para visualización.
• DEBE declarar las características android.software.leanback y android.hardware.type.television [ Recursos, 3 ].

Dispositivo Android Watch se refiere a una implementación de dispositivo Android destinada a usarse en el cuerpo, quizás en la muñeca, y:

• DEBE tener una pantalla con una longitud diagonal física en el rango de 1,1 a 2,5 pulgadas.
• DEBE declarar la característica android.hardware.type.watch.
• DEBE admitir uiMode = UI_MODE_TYPE_WATCH [ Recursos, 4 ].

La implementación de Android Automotive se refiere a la unidad principal de un vehículo que ejecuta Android como sistema operativo para parte o la totalidad del sistema y/o la funcionalidad de infoentretenimiento. Implementaciones de Android Automotive:

• DEBE declarar la característica android.hardware.type.automotive.
• DEBE admitir uiMode = UI_MODE_TYPE_CAR [ Recursos, 5 ].

Todas las implementaciones de dispositivos Android que no encajan en ninguno de los tipos de dispositivos anteriores DEBEN cumplir con todos los requisitos de este documento para ser compatibles con Android 6.0, a menos que se describa explícitamente que el requisito solo es aplicable a un tipo de dispositivo Android específico desde arriba.

2.1 Configuraciones del dispositivo

Este es un resumen de las principales diferencias en la configuración de hardware por tipo de dispositivo. (Las celdas vacías indican "MAYO"). No todas las configuraciones están cubiertas en esta tabla; consulte las secciones de hardware relevantes para obtener más detalles.

Categoría	Característica	Sección	Mano	Televisión	Mirar	Automotor	Otro
Aporte	pad direccional	7.2.2. Navegación no táctil		DEBE
	Pantalla táctil	7.2.4. Entrada de pantalla táctil	DEBE		DEBE		DEBERÍA
	Micrófono	7.8.1. Micrófono	DEBE	DEBERÍA	DEBE	DEBE	DEBERÍA
Sensores	Acelerómetro	7.3.1 Acelerómetro	DEBERÍA		DEBERÍA		DEBERÍA
	GPS	7.3.3. GPS	DEBERÍA			DEBERÍA
Conectividad	Wifi	7.4.2. IEEE 802.11	DEBERÍA	DEBE		DEBERÍA	DEBERÍA
	Wi-Fi directo	7.4.2.1. Wi-Fi directo	DEBERÍA	DEBERÍA			DEBERÍA
	Bluetooth	7.4.3. Bluetooth	DEBERÍA	DEBE	DEBE	DEBE	DEBERÍA
	Bluetooth de baja energía	7.4.3. Bluetooth	DEBERÍA	DEBE	DEBERÍA	DEBERÍA	DEBERÍA
	Modo periférico/host USB	7.7. USB	DEBERÍA			DEBERÍA	DEBERÍA
Producción	Puertos de salida de altavoz y/o audio	7.8.2. Salida de audio	DEBE	DEBE		DEBE	DEBE

3.software

3.1. Compatibilidad de API administrada

El entorno de ejecución de bytecode administrado de Dalvik es el vehículo principal para las aplicaciones de Android. La interfaz de programación de aplicaciones (API) de Android es el conjunto de interfaces de la plataforma Android expuestas a aplicaciones que se ejecutan en el entorno de ejecución administrado. Las implementaciones de dispositivos DEBEN proporcionar implementaciones completas, incluidos todos los comportamientos documentados, de cualquier API documentada expuesta por el SDK de Android [ Recursos, 6 ] o cualquier API decorada con el marcador "@SystemApi" en el código fuente de Android.

Las implementaciones de dispositivos NO DEBEN omitir ninguna API administrada, alterar las interfaces o firmas de API, desviarse del comportamiento documentado ni incluir operaciones no operativas, excepto donde lo permita específicamente esta Definición de compatibilidad.

Esta Definición de compatibilidad permite que las implementaciones de dispositivos omitan algunos tipos de hardware para los cuales Android incluye API. En tales casos, las API DEBEN seguir estando presentes y comportarse de forma razonable. Consulte la sección 7 para conocer los requisitos específicos para este escenario.

3.2. Compatibilidad de API suave

Además de las API administradas de la sección 3.1 , Android también incluye una importante API "suave" solo en tiempo de ejecución, en forma de intenciones, permisos y aspectos similares de las aplicaciones de Android que no se pueden aplicar en el momento de la compilación de la aplicación.

3.2.1. Permisos

Los implementadores de dispositivos DEBEN admitir y hacer cumplir todas las constantes de permisos según lo documentado en la página de referencia de permisos [ Recursos, 7 ]. Tenga en cuenta que la sección 9 enumera requisitos adicionales relacionados con el modelo de seguridad de Android.

3.2.2. Parámetros de construcción

Las API de Android incluyen una serie de constantes en la clase android.os.Build [ Recursos, 8 ] que están destinadas a describir el dispositivo actual. Para proporcionar valores coherentes y significativos en todas las implementaciones de dispositivos, la siguiente tabla incluye restricciones adicionales sobre los formatos de estos valores a los que DEBEN ajustarse las implementaciones de dispositivos.

Parámetro	Detalles
VERSIÓN.LIBERACIÓN	La versión del sistema Android que se está ejecutando actualmente, en formato legible por humanos. Este campo DEBE tener uno de los valores de cadena definidos en [ Recursos, 9 ].
VERSIÓN.SDK	La versión del sistema Android que se ejecuta actualmente, en un formato accesible al código de aplicación de terceros. Para Android 6.0, este campo DEBE tener el valor entero 23.
VERSIÓN.SDK_INT	La versión del sistema Android que se ejecuta actualmente, en un formato accesible al código de aplicación de terceros. Para Android 6.0, este campo DEBE tener el valor entero 23.
VERSIÓN.INCREMENTAL	Un valor elegido por el implementador del dispositivo que designa la compilación específica del sistema Android que se está ejecutando actualmente, en formato legible por humanos. Este valor NO DEBE reutilizarse para diferentes compilaciones disponibles para los usuarios finales. Un uso típico de este campo es indicar qué número de compilación o identificador de cambio de control de fuente se utilizó para generar la compilación. No hay requisitos sobre el formato específico de este campo, excepto que NO DEBE ser nulo o una cadena vacía ("").
JUNTA	Un valor elegido por el implementador del dispositivo que identifica el hardware interno específico utilizado por el dispositivo, en formato legible por humanos. Un posible uso de este campo es indicar la revisión específica de la placa que alimenta el dispositivo. El valor de este campo DEBE poder codificarse como ASCII de 7 bits y coincidir con la expresión regular “^[a-zA-Z0-9_-]+$”.
MARCA	Un valor que refleja la marca asociada con el dispositivo tal como la conocen los usuarios finales. DEBE estar en formato legible por humanos y DEBE representar al fabricante del dispositivo o la marca de la empresa bajo la cual se comercializa el dispositivo. El valor de este campo DEBE poder codificarse como ASCII de 7 bits y coincidir con la expresión regular “^[a-zA-Z0-9_-]+$”.
SUPPORTED_ABIS	El nombre del conjunto de instrucciones (tipo de CPU + convención ABI) del código nativo. Ver sección 3.3. Compatibilidad de API nativa .
SOPORTE_32_BIT_ABIS	El nombre del conjunto de instrucciones (tipo de CPU + convención ABI) del código nativo. Ver sección 3.3. Compatibilidad de API nativa .
SOPORTE_64_BIT_ABIS	El nombre del segundo conjunto de instrucciones (tipo de CPU + convención ABI) del código nativo. Ver sección 3.3. Compatibilidad de API nativa .
CPU_ABI	El nombre del conjunto de instrucciones (tipo de CPU + convención ABI) del código nativo. Ver sección 3.3. Compatibilidad de API nativa .
CPU_ABI2	El nombre del segundo conjunto de instrucciones (tipo de CPU + convención ABI) del código nativo. Ver sección 3.3. Compatibilidad de API nativa .
DISPOSITIVO	Un valor elegido por el implementador del dispositivo que contiene el nombre del desarrollo o el nombre del código que identifica la configuración de las características del hardware y el diseño industrial del dispositivo. El valor de este campo DEBE poder codificarse como ASCII de 7 bits y coincidir con la expresión regular “^[a-zA-Z0-9_-]+$”.
HUELLA DACTILAR	Una cadena que identifica de forma única esta compilación. DEBE ser razonablemente legible por humanos. DEBE seguir esta plantilla: $(MARCA)/$(PRODUCTO)/ $(DISPOSITIVO):$(VERSIÓN.LIBERACIÓN)/$(ID)/$(VERSIÓN.INCREMENTAL):$(TIPO)/$(TAGS) Por ejemplo: cima/miproducto/ midispositivo:6.0/LMYXX/3359:userdebug/test-keys La huella digital NO DEBE incluir espacios en blanco. Si otros campos incluidos en la plantilla anterior tienen espacios en blanco, DEBEN reemplazarse en la huella digital de compilación con otro carácter, como el carácter de guión bajo ("_"). El valor de este campo DEBE poder codificarse como ASCII de 7 bits.
HARDWARE	El nombre del hardware (de la línea de comando del kernel o /proc). DEBE ser razonablemente legible por humanos. El valor de este campo DEBE poder codificarse como ASCII de 7 bits y coincidir con la expresión regular “^[a-zA-Z0-9_-]+$”.
ANFITRIÓN	Una cadena que identifica de forma única el host en el que se creó la compilación, en formato legible por humanos. No hay requisitos sobre el formato específico de este campo, excepto que NO DEBE ser nulo o una cadena vacía ("").
IDENTIFICACIÓN	Un identificador elegido por el implementador del dispositivo para hacer referencia a una versión específica, en formato legible por humanos. Este campo puede ser el mismo que android.os.Build.VERSION.INCREMENTAL, pero DEBE ser un valor suficientemente significativo para que los usuarios finales distingan entre compilaciones de software. El valor de este campo DEBE poder codificarse como ASCII de 7 bits y coincidir con la expresión regular “^[a-zA-Z0-9._-]+$”.
FABRICANTE	El nombre comercial del fabricante de equipos originales (OEM) del producto. No hay requisitos sobre el formato específico de este campo, excepto que NO DEBE ser nulo o una cadena vacía ("").
MODELO	Un valor elegido por el implementador del dispositivo que contiene el nombre del dispositivo tal como lo conoce el usuario final. Este DEBE ser el mismo nombre con el que se comercializa y vende el dispositivo a los usuarios finales. No hay requisitos sobre el formato específico de este campo, excepto que NO DEBE ser nulo o una cadena vacía ("").
PRODUCTO	Un valor elegido por el implementador del dispositivo que contiene el nombre de desarrollo o el nombre en código del producto específico (SKU) que DEBE ser único dentro de la misma marca. DEBE ser legible por humanos, pero no necesariamente está destinado a ser visto por usuarios finales. El valor de este campo DEBE poder codificarse como ASCII de 7 bits y coincidir con la expresión regular “^[a-zA-Z0-9_-]+$”.
DE SERIE	Un número de serie de hardware, que DEBE estar disponible y ser único en todos los dispositivos con el mismo MODELO y FABRICANTE. El valor de este campo DEBE poder codificarse como ASCII de 7 bits y coincidir con la expresión regular “^([a-zA-Z0-9]{6,20})$”.
ETIQUETAS	Una lista de etiquetas separadas por comas elegidas por el implementador del dispositivo que distingue aún más la compilación. Este campo DEBE tener uno de los valores correspondientes a las tres configuraciones típicas de firma de la plataforma Android: claves de lanzamiento, claves de desarrollo y claves de prueba.
TIEMPO	Un valor que representa la marca de tiempo de cuando ocurrió la compilación.
TIPO	Un valor elegido por el implementador del dispositivo que especifica la configuración de tiempo de ejecución de la compilación. Este campo DEBE tener uno de los valores correspondientes a las tres configuraciones típicas de tiempo de ejecución de Android: usuario, usuariodebug o eng.
USUARIO	Un nombre o ID de usuario del usuario (o usuario automatizado) que generó la compilación. No hay requisitos sobre el formato específico de este campo, excepto que NO DEBE ser nulo o una cadena vacía ("").
PARCHE_SEGURIDAD	Un valor que indica el nivel del parche de seguridad de una compilación. DEBE significar que la compilación incluye todos los parches de seguridad emitidos a través del Boletín de Seguridad Pública de Android designado. DEBE tener el formato [AAAA-MM-DD], que coincida con una de las cadenas de nivel de parche de seguridad de Android de los boletines de seguridad pública , por ejemplo, "2015-11-01".
SO_BASE	Un valor que representa el parámetro FINGERPRINT de la compilación que, por lo demás, es idéntico a esta compilación, excepto por los parches proporcionados en el Boletín de seguridad pública de Android. DEBE informar el valor correcto y, si dicha compilación no existe, informar una cadena vacía ("").

3.2.3. Compatibilidad de intenciones

Las implementaciones de dispositivos DEBEN respetar el sistema de intención de acoplamiento flexible de Android, como se describe en las secciones siguientes. Por "honrado" se entiende que el implementador del dispositivo DEBE proporcionar una actividad o servicio de Android que especifique un filtro de intención coincidente que se vincule e implemente el comportamiento correcto para cada patrón de intención especificado.

3.2.3.1. Intenciones principales de la aplicación

Los intents de Android permiten que los componentes de la aplicación soliciten funcionalidad de otros componentes de Android. El proyecto ascendente de Android incluye una lista de aplicaciones consideradas aplicaciones principales de Android, que implementa varios patrones de intención para realizar acciones comunes. Las aplicaciones principales de Android son:

• Reloj de escritorio
• Navegador
• Calendario
• Contactos
• Galería
• Búsqueda global
• Lanzacohetes
• Música
• Ajustes

Las implementaciones de dispositivos DEBEN incluir las aplicaciones principales de Android según corresponda, pero DEBEN incluir un componente que implemente los mismos patrones de intención definidos por todos los componentes de Actividad o Servicio "públicos" de estas aplicaciones principales de Android. Tenga en cuenta que los componentes de Actividad o Servicio se consideran "públicos" cuando el atributo android:exported está ausente o tiene el valor verdadero.

3.2.3.2. Resolución de intención

Como Android es una plataforma extensible, las implementaciones de dispositivos DEBEN permitir que cada patrón de intención al que se hace referencia en la sección 3.2.3.1 sea anulado por aplicaciones de terceros. La implementación de código abierto de Android permite esto de forma predeterminada; Los implementadores de dispositivos NO DEBEN otorgar privilegios especiales al uso de estos patrones de intención por parte de las aplicaciones del sistema, ni evitar que aplicaciones de terceros se vinculen y asuman el control de estos patrones. Esta prohibición incluye específicamente, entre otras, la desactivación de la interfaz de usuario "Selector" que permite al usuario seleccionar entre múltiples aplicaciones que manejan el mismo patrón de intención.

Las implementaciones de dispositivos DEBEN proporcionar una interfaz de usuario para que los usuarios modifiquen la actividad predeterminada para los intentos.

Sin embargo, las implementaciones de dispositivos PUEDEN proporcionar actividades predeterminadas para patrones de URI específicos (por ejemplo, http://play.google.com) cuando la actividad predeterminada proporciona un atributo más específico para el URI de datos. Por ejemplo, un patrón de filtro de intención que especifica el URI de datos “http://www.android.com” es más específico que el patrón de intención principal del navegador para “http://”.

Android también incluye un mecanismo para que aplicaciones de terceros declaren un comportamiento de vinculación de aplicaciones predeterminado autorizado para ciertos tipos de intenciones de URI web [ Recursos, 140 ]. Cuando dichas declaraciones autorizadas se definen en los patrones de filtro de intención de una aplicación, las implementaciones del dispositivo:

• DEBE intentar validar cualquier filtro de intención realizando los pasos de validación definidos en la especificación de Enlaces de Activos Digitales [ Recursos, 141 ] implementada por el Administrador de Paquetes en el Proyecto de Código Abierto de Android ascendente.
• DEBE intentar la validación de los filtros de intención durante la instalación de la aplicación y configurar todos los filtros de intención de UIR validados correctamente como controladores de aplicaciones predeterminados para sus UIR.
• PUEDE establecer filtros de intención de URI específicos como controladores de aplicaciones predeterminados para sus URI, si se verifican correctamente pero otros filtros de URI candidatos no superan la verificación. Si la implementación de un dispositivo hace esto, DEBE proporcionar al usuario anulaciones de patrones por URI apropiadas en el menú de configuración.
• DEBE proporcionar al usuario controles de enlaces de aplicaciones por aplicación en Configuración de la siguiente manera:
  • El usuario DEBE poder anular de manera integral el comportamiento predeterminado de los enlaces de la aplicación para que una aplicación esté: siempre abierta, siempre preguntando o nunca abierta, lo que debe aplicarse a todos los filtros de intención de URI candidatos por igual.
  • El usuario DEBE poder ver una lista de los filtros de intención de URI candidatos.
  • La implementación del dispositivo PUEDE proporcionar al usuario la capacidad de anular filtros de intención de URI candidatos específicos que se verificaron con éxito, por filtro por intención.
  • La implementación del dispositivo DEBE proporcionar a los usuarios la capacidad de ver y anular filtros de intención de URI candidatos específicos si la implementación del dispositivo permite que algunos filtros de intención de URI candidatos tengan éxito en la verificación mientras que otros pueden fallar.

3.2.3.3. Espacios de nombres de intención

Las implementaciones de dispositivos NO DEBEN incluir ningún componente de Android que respete cualquier intención nueva o patrón de intención de transmisión utilizando una ACCIÓN, CATEGORÍA u otra cadena clave en el espacio de nombres android.* o com.android.*. Los implementadores de dispositivos NO DEBEN incluir ningún componente de Android que respete cualquier intención nueva o patrón de intención de transmisión utilizando una ACCIÓN, CATEGORÍA u otra cadena clave en un espacio de paquete que pertenezca a otra organización. Los implementadores de dispositivos NO DEBEN alterar ni ampliar ninguno de los patrones de intención utilizados por las aplicaciones principales enumeradas en la sección 3.2.3.1 . Las implementaciones de dispositivos PUEDEN incluir patrones de intención que utilizan espacios de nombres asociados clara y obviamente con su propia organización. Esta prohibición es análoga a la especificada para las clases de lenguaje Java en la sección 3.6 .

3.2.3.4. Intenciones de transmisión

Las aplicaciones de terceros dependen de la plataforma para transmitir ciertos intentos de notificarles sobre cambios en el entorno de hardware o software. Los dispositivos compatibles con Android DEBEN transmitir las intenciones de transmisión pública en respuesta a los eventos apropiados del sistema. Los intentos de transmisión se describen en la documentación del SDK.

3.2.3.5. Configuración predeterminada de la aplicación

Android incluye configuraciones que brindan a los usuarios una manera fácil de seleccionar sus aplicaciones predeterminadas, por ejemplo, para la pantalla de inicio o SMS. Cuando tenga sentido, las implementaciones de dispositivos DEBEN proporcionar un menú de configuración similar y ser compatibles con el patrón de filtro de intención y los métodos API que se describen en la documentación del SDK como se muestra a continuación.

Implementaciones de dispositivos:

• DEBE respetar la intención de android.settings.HOME_SETTINGS de mostrar un menú de configuración de aplicación predeterminado para la pantalla de inicio, si la implementación del dispositivo informa android.software.home_screen [ Recursos, 10 ]
• DEBE proporcionar un menú de configuración que llame a la intención android.provider.Telephony.ACTION_CHANGE_DEFAULT para mostrar un cuadro de diálogo para cambiar la aplicación de SMS predeterminada, si la implementación del dispositivo informa android.hardware.telephony [ Recursos, 11 ]
• DEBE respetar la intención de android.settings.NFC_PAYMENT_SETTINGS de mostrar un menú de configuración de aplicación predeterminado para Tap and Pay, si la implementación del dispositivo informa android.hardware.nfc.hce [ Recursos, 10 ]

3.3. Compatibilidad API nativa

3.3.1. Interfaces binarias de aplicaciones

El código de bytes de Dalvik administrado puede llamar al código nativo proporcionado en el archivo .apk de la aplicación como un archivo ELF .so compilado para la arquitectura de hardware del dispositivo adecuada. Como el código nativo depende en gran medida de la tecnología del procesador subyacente, Android define una serie de interfaces binarias de aplicaciones (ABI) en el NDK de Android. Las implementaciones de dispositivos DEBEN ser compatibles con una o más ABI definidas y DEBEN implementar compatibilidad con el NDK de Android, como se muestra a continuación.

Si la implementación de un dispositivo incluye soporte para una ABI de Android,:

• DEBE incluir soporte para el código que se ejecuta en el entorno administrado para llamar al código nativo, utilizando la semántica estándar de la interfaz nativa de Java (JNI).
• DEBE ser compatible con el código fuente (es decir, compatible con el encabezado) y con los binarios (para ABI) con cada biblioteca requerida en la lista siguiente
• DEBE admitir la ABI de 32 bits equivalente si se admite alguna ABI de 64 bits
• DEBE informar con precisión la interfaz binaria de aplicación (ABI) nativa admitida por el dispositivo, a través de los parámetros android.os.Build.SUPPORTED_ABIS, android.os.Build.SUPPORTED_32_BIT_ABIS y android.os.Build.SUPPORTED_64_BIT_ABIS, cada uno de los cuales es una lista separada por comas de ABI ordenados del más al menos preferido
• DEBE informar, a través de los parámetros anteriores, solo aquellas ABI documentadas y descritas en la última versión de la documentación de administración de ABI del NDK de Android [ Recursos, 12 ], y DEBE incluir soporte para la extensión SIMD avanzada (también conocida como NEON) [ Recursos, 13 ]
• DEBE construirse utilizando el código fuente y los archivos de encabezado disponibles en el proyecto de código abierto de Android.

Las siguientes API de código nativo DEBEN estar disponibles para aplicaciones que incluyen código nativo:

• libc (biblioteca C)
• libm (biblioteca de matemáticas)
• Soporte mínimo para C++
• interfaz JNI
• liblog (registro de Android)
• libz (compresión Zlib)
• libdl (enlazador dinámico)
• libGLESv1_CM.so (OpenGL ES 1.x)
• libGLESv2.so (OpenGL ES 2.0)
• libGLESv3.so (OpenGL ES 3.x)
• libEGL.so (gestión de superficie nativa OpenGL)
• libjnigraphics.so
• libOpenSLES.so (soporte de audio OpenSL ES 1.0.1)
• libOpenMAXAL.so (soporte para OpenMAX AL 1.0.1)
• libandroid.so (soporte de actividad nativo de Android)
• libmediandk.so (soporte de API de medios nativos)
• Soporte para OpenGL, como se describe a continuación

Tenga en cuenta que las versiones futuras del NDK de Android pueden incluir compatibilidad con ABI adicionales. Si la implementación de un dispositivo no es compatible con una ABI predefinida existente, NO DEBE informar soporte para ninguna ABI en absoluto.

Tenga en cuenta que las implementaciones de dispositivos DEBEN incluir libGLESv3.so y DEBE vincular simbólicamente (enlace simbólico) a libGLESv2.so. a su vez, DEBE exportar todos los símbolos de función de OpenGL ES 3.1 y Android Extension Pack [ Recursos, 14 ] tal como se define en la versión android-21 del NDK. Aunque todos los símbolos deben estar presentes, sólo se deben implementar completamente las funciones correspondientes a las versiones y extensiones de OpenGL ES realmente compatibles con el dispositivo.

Las implementaciones de dispositivos, si incluyen una biblioteca nativa con el nombre libvulkan.so, DEBEN exportar símbolos de funciones y proporcionar una implementación de la API Vulkan 1.0 y las extensiones VK_KHR_surface, VK_KHR_swapchain y VK_KHR_android_surface según lo define Khronos Group y pasan las pruebas de conformidad de Khronos.

La compatibilidad del código nativo es un desafío. Por este motivo, se RECOMIENDA ENCARECIDAMENTE a los implementadores de dispositivos que utilicen las implementaciones de las bibliotecas enumeradas anteriormente del Proyecto de código abierto de Android.

3.3.2. Compatibilidad con código nativo ARM de 32 bits

La arquitectura ARMv8 desaprueba varias operaciones de la CPU, incluidas algunas operaciones utilizadas en el código nativo existente. En dispositivos ARM de 64 bits, las siguientes operaciones obsoletas DEBEN permanecer disponibles para el código ARM nativo de 32 bits, ya sea mediante soporte de CPU nativo o mediante emulación de software:

• Instrucciones SWP y SWPB
• Instrucción ESTABLECER
• Operaciones de barrera CP15ISB, CP15DSB y CP15DMB

Las versiones heredadas del NDK de Android usaban /proc/cpuinfo para descubrir funciones de CPU a partir de código nativo ARM de 32 bits. Para compatibilidad con aplicaciones creadas con este NDK, los dispositivos DEBEN incluir las siguientes líneas en /proc/cpuinfo cuando lo leen aplicaciones ARM de 32 bits:

• "Características: ", seguido de una lista de las funciones opcionales de la CPU ARMv7 admitidas por el dispositivo.
• "Arquitectura de CPU:", seguido de un número entero que describe la arquitectura ARM más compatible con el dispositivo (por ejemplo, "8" para dispositivos ARMv8)

Estos requisitos solo se aplican cuando /proc/cpuinfo es leído por aplicaciones ARM de 32 bits. Los dispositivos no DEBEN alterar /proc/cpuinfo cuando los leen aplicaciones ARM o no ARM de 64 bits.

3.4. Compatibilidad web

3.4.1. Compatibilidad con WebView

La característica de la plataforma android.software.webview DEBE informarse en cualquier dispositivo que proporcione una implementación completa de la API android.webkit.WebView, y NO DEBE informarse en dispositivos sin una implementación completa de la API. La implementación de Android Open Source utiliza código del Proyecto Chromium para implementar android.webkit.WebView [ Recursos, 15 ]. Debido a que no es factible desarrollar un conjunto de pruebas integral para un sistema de renderizado web, los implementadores de dispositivos DEBEN usar la compilación ascendente específica de Chromium en la implementación de WebView. Específicamente:

• Las implementaciones del dispositivo android.webkit.WebView DEBEN basarse en la compilación de Chromium del proyecto de código abierto de Android para Android 6.0. Esta compilación incluye un conjunto específico de funcionalidades y correcciones de seguridad para WebView [ Recursos, 16 ].
• La cadena del agente de usuario informada por WebView DEBE tener este formato:

  Mozilla/5.0 (Linux; Android $(VERSIÓN); $(MODEL) Build/$(BUILD); wv) AppleWebKit/537.36 (KHTML, como Gecko) Versión/4.0 $(CHROMIUM_VER) Mobile Safari/537.36

  • El valor de la cadena $(VERSION) DEBE ser el mismo que el valor de android.os.Build.VERSION.RELEASE.
  • El valor de la cadena $(MODEL) DEBE ser el mismo que el valor de android.os.Build.MODEL.
  • El valor de la cadena $(BUILD) DEBE ser el mismo que el valor de android.os.Build.ID.
  • El valor de la cadena $(CHROMIUM_VER) DEBE ser la versión de Chromium en el proyecto de código abierto de Android ascendente.
  • Las implementaciones de dispositivos PUEDEN omitir Mobile en la cadena del agente de usuario.

El componente WebView DEBE incluir soporte para tantas funciones HTML5 como sea posible y, si es compatible, la función DEBE ajustarse a la especificación HTML5 [ Recursos, 17 ].

3.4.2. Compatibilidad del navegador

El navegador independiente PUEDE basarse en una tecnología de navegador distinta de WebKit. Sin embargo, incluso si se utiliza una aplicación de navegador alternativa, el componente android.webkit.WebView proporcionado a aplicaciones de terceros DEBE estar basado en WebKit, como se describe en la sección 3.4.1 .

Las implementaciones PUEDEN incluir una cadena de agente de usuario personalizada en la aplicación de navegador independiente.

La aplicación de navegador independiente (ya sea basada en la aplicación de navegador WebKit anterior o en un reemplazo de terceros) DEBE incluir soporte para la mayor cantidad de HTML5 [ Recursos, 17 ] posible. Como mínimo, las implementaciones de dispositivos DEBEN admitir cada una de estas API asociadas con HTML5:

• caché de aplicaciones/operación sin conexión [ Recursos, 18 ]
• la etiqueta <video> [ Recursos, 19 ]
• geolocalización [ Recursos, 20 ]

Además, las implementaciones de dispositivos DEBEN admitir la API de almacenamiento web HTML5/W3C [ Recursos, 21 ], y DEBEN admitir la API HTML5/W3C IndexedDB [ Recursos, 22 ]. Tenga en cuenta que a medida que los organismos de estándares de desarrollo web están haciendo la transición para favorecer IndexedDB sobre el almacenamiento web, se espera que IndexedDB se convierta en un componente requerido en una versión futura de Android.

3.5. Compatibilidad de comportamiento de API

Los comportamientos de cada uno de los tipos de API (administrado, software, nativo y web) deben ser coherentes con la implementación preferida del Proyecto de código abierto de Android ascendente [ Recursos, 2 ]. Algunas áreas específicas de compatibilidad son:

• Los dispositivos NO DEBEN cambiar el comportamiento o la semántica de una intención estándar.
• Los dispositivos NO DEBEN alterar el ciclo de vida o la semántica del ciclo de vida de un tipo particular de componente del sistema (como Servicio, Actividad, Proveedor de contenido, etc.).
• Los dispositivos NO DEBEN cambiar la semántica de un permiso estándar.

La lista anterior no es exhaustiva. El Compatibility Test Suite (CTS) prueba partes importantes de la plataforma para determinar la compatibilidad del comportamiento, pero no todas. Es responsabilidad del implementador garantizar la compatibilidad del comportamiento con el Proyecto de código abierto de Android. Por esta razón, los implementadores de dispositivos DEBEN utilizar el código fuente disponible a través del Proyecto de código abierto de Android siempre que sea posible, en lugar de volver a implementar partes importantes del sistema.

3.6. Espacios de nombres API

Android sigue las convenciones de espacio de nombres de paquetes y clases definidas por el lenguaje de programación Java. Para garantizar la compatibilidad con aplicaciones de terceros, los implementadores de dispositivos NO DEBEN realizar modificaciones prohibidas (ver a continuación) en estos espacios de nombres de paquetes:

• Java.*
• javax.*
• sol.*
• androide.*
• com.android.*

Las modificaciones prohibidas incluyen :

• Las implementaciones de dispositivos NO DEBEN modificar las API expuestas públicamente en la plataforma Android cambiando cualquier método o firma de clase, o eliminando clases o campos de clase.
• Los implementadores de dispositivos PUEDEN modificar la implementación subyacente de las API, pero dichas modificaciones NO DEBEN afectar el comportamiento declarado ni la firma en lenguaje Java de las API expuestas públicamente.
• Los implementadores de dispositivos NO DEBEN agregar ningún elemento expuesto públicamente (como clases o interfaces, o campos o métodos a clases o interfaces existentes) a las API anteriores.

Un "elemento expuesto públicamente" es cualquier construcción que no esté decorada con el marcador "@hide" como se usa en el código fuente de Android. En otras palabras, los implementadores de dispositivos NO DEBEN exponer nuevas API ni alterar las API existentes en los espacios de nombres mencionados anteriormente. Los implementadores de dispositivos PUEDEN realizar modificaciones solo internas, pero esas modificaciones NO DEBEN publicitarse ni exponerse de otro modo a los desarrolladores.

Los implementadores de dispositivos PUEDEN agregar API personalizadas, pero dichas API NO DEBEN estar en un espacio de nombres que sea propiedad de otra organización o que haga referencia a ella. Por ejemplo, los implementadores de dispositivos NO DEBEN agregar API al espacio de nombres com.google.* o similar: solo Google puede hacerlo. Del mismo modo, Google no debe agregar API a los espacios de nombres de otras compañías. Además, si una implementación de un dispositivo incluye API personalizadas fuera del espacio de nombres de Android estándar, esas API deben empaquetarse en una biblioteca compartida de Android para que solo las aplicaciones que las usen explícitamente (a través del LT; use-bibrarygt; mecanismo) se ve afectadas por el aumento de la memoria Uso de tales API.

Si un implementador de dispositivo propone mejorar uno de los espacios de nombres de paquetes anteriores (como agregar una nueva funcionalidad útil a una API existente, o agregar una nueva API), el implementador debe visitar Source.Android.com y comenzar el proceso para contribuir con cambios y código, de acuerdo con la información en ese sitio.

Tenga en cuenta que las restricciones anteriores corresponden a convenciones estándar para nombrar API en el lenguaje de programación Java; Esta sección simplemente tiene como objetivo reforzar esas convenciones y hacerlas vinculantes a través de la inclusión en esta definición de compatibilidad.

3.7. Compatibilidad de tiempo de ejecución

Las implementaciones de dispositivos deben admitir el formato completo de Dalvik Ejecutable (DEX) y la especificación de Bytecode Dalvik y la semántica [ recursos, 23 ]. Los implementadores de dispositivos deben usar ART, la implementación de referencia aguas arriba del formato ejecutable de Dalvik y el sistema de gestión de paquetes de la implementación de referencia.

Las implementaciones de dispositivos deben configurar Dalvik Runtimes para asignar la memoria de acuerdo con la plataforma Android ascendente, y según lo especificado por la siguiente tabla. (Consulte la Sección 7.1.1 para ver las definiciones de tamaño de pantalla y densidad de pantalla).

Tenga en cuenta que los valores de memoria especificados a continuación se consideran valores mínimos y las implementaciones de dispositivos pueden asignar más memoria por aplicación.

Diseño de pantalla	Densidad de la pantalla	Memoria de aplicación mínima
Reloj Android	120 DPI (LDPI)	32MB
	160 DPI (MDPI)
	213 DPI (TVDPI)
	240 DPI (HDPI)	36MB
	280 DPI (280dpi)
	320 DPI (XHDPI)	48 MB
	360 DPI (360dpi)
	400 DPI (400dpi)	56MB
	420 DPI (420dpi)	64MB
	480 DPI (xxhdpi)	88 MB
	560 DPI (560dpi)	112MB
	640 DPI (xxxhdpi)	154 MB
pequeño/normal	120 DPI (LDPI)	32MB
	160 DPI (MDPI)
	213 DPI (TVDPI)	48 MB
	240 DPI (HDPI)
	280 DPI (280dpi)
	320 DPI (XHDPI)	80MB
	360 DPI (360dpi)
	400 DPI (400dpi)	96MB
	420 DPI (420dpi)	112MB
	480 DPI (xxhdpi)	128MB
	560 DPI (560dpi)	192MB
	640 DPI (xxxhdpi)	256MB
grande	120 DPI (LDPI)	32MB
	160 DPI (MDPI)	48 MB
	213 DPI (TVDPI)	80MB
	240 DPI (HDPI)
	280 DPI (280dpi)	96MB
	320 DPI (XHDPI)	128MB
	360 DPI (360dpi)	160 MB
	400 DPI (400dpi)	192MB
	420 DPI (420dpi)	228MB
	480 DPI (xxhdpi)	256MB
	560 DPI (560dpi)	384MB
	640 DPI (xxxhdpi)	512MB
extra grande	120 DPI (LDPI)	48 MB
	160 DPI (MDPI)	80MB
	213 DPI (TVDPI)	96MB
	240 DPI (HDPI)
	280 DPI (280dpi)	144MB
	320 DPI (XHDPI)	192MB
	360 DPI (360dpi)	240MB
	400 DPI (400dpi)	288MB
	420 DPI (420dpi)	336 MB
	480 DPI (xxhdpi)	384MB
	560 DPI (560dpi)	576 MB
	640 DPI (xxxhdpi)	768MB

3.8. Compatibilidad de la interfaz de usuario

3.8.1. Lanzador (pantalla de inicio)

Android incluye una aplicación de lanzamiento (pantalla de inicio) y soporte para aplicaciones de terceros para reemplazar el lanzador de dispositivos (pantalla de inicio). Las implementaciones de dispositivos que permiten que las aplicaciones de terceros reemplazaran la pantalla de inicio del dispositivo deben declarar la función de la plataforma android.software.home_screen.

3.8.2. widgets

Android define un tipo de componente y la API y el ciclo de vida correspondiente que permite que las aplicaciones expongan un "AppWidget" al usuario final [ recursos, 24 ] una característica que se recomienda encarecidamente ser compatible con las implementaciones de dispositivos de mano. Las implementaciones de dispositivos que admiten integrar widgets en la pantalla de inicio deben cumplir con los siguientes requisitos y declarar soporte para la función de la plataforma android.software.app_widgets.

• Los lanzadores de dispositivos deben incluir soporte incorporado para AppWidgets y exponer las posibilidades de la interfaz de usuario para agregar, configurar, ver y eliminar AppWidgets directamente dentro del lanzador.
• Las implementaciones del dispositivo deben ser capaces de hacer widgets que sean 4 x 4 en el tamaño de la cuadrícula estándar. Consulte las pautas de diseño de widget de la aplicación en la documentación SDK de Android [ recursos, 24 ] para más detalles.
• Las implementaciones de dispositivos que incluyen soporte para la pantalla de bloqueo pueden admitir widgets de aplicación en la pantalla de bloqueo.

3.8.3. Notificaciones

Android incluye API que permiten a los desarrolladores notificar a los usuarios de eventos notables [ recursos, 25 ], utilizando funciones de hardware y software del dispositivo.

Algunas API permiten a las aplicaciones realizar notificaciones o atraer atención utilizando hardware, específicamente sólido, vibración y luz. Las implementaciones de dispositivos deben admitir notificaciones que usan características de hardware, como se describe en la documentación SDK y en la medida posible con el hardware de implementación del dispositivo. Por ejemplo, si una implementación de un dispositivo incluye un vibrador, debe implementar correctamente las API de vibración. Si una implementación de un dispositivo carece de hardware, las API correspondientes deben implementarse como NO-OPS. Este comportamiento se detalla aún más en la Sección 7 .

Además, la implementación debe representar correctamente todos los recursos (iconos, archivos de animación, etc.) proporcionados en las API [ recursos, 26 ], o en la Guía de estilo de icono de la barra de estado/sistema [ recursos, 27 ], que en el caso de un El dispositivo de televisión Android incluye la posibilidad de no mostrar las notificaciones. Los implementadores de dispositivos pueden proporcionar una experiencia de usuario alternativa para las notificaciones que la proporcionada por la implementación de código abierto de Android de referencia; Sin embargo, tales sistemas de notificación alternativa deben respaldar los recursos de notificación existentes, como se indicó anteriormente.

Android incluye soporte para diversas notificaciones, como:

• Notificaciones ricas . Vistas interactivas para notificaciones continuas.
• Notificaciones de la cabeza . Vistas interactivas Los usuarios pueden actuar o descartar sin dejar la aplicación actual.
• Notificaciones de pantalla de bloqueo . Notificaciones que se muestran sobre una pantalla de bloqueo con control granular sobre la visibilidad.

Las implementaciones de dispositivos de Android, cuando tales notificaciones se hacen visibles, deben ejecutar correctamente las notificaciones ricas y frecuentes e incluir el título/nombre, icono, texto como se documenta en las API de Android [ recursos, 28 ].

Android incluye las API del servicio de escucha de notificaciones que permiten que las aplicaciones (una vez habilitadas explícitamente por el usuario) reciban una copia de todas las notificaciones a medida que se publican o se actualizan. Las implementaciones de dispositivos deben enviar notificaciones de manera correcta y rápida en su totalidad a todos estos servicios de oyentes instalados y habilitados para el usuario, incluidos todos y cada uno de los metadatos adjuntos al objeto de notificación.

3.8.4. Buscar

Android incluye API [ recursos, 29 ] que permiten a los desarrolladores incorporar la búsqueda en sus aplicaciones y exponer los datos de su aplicación en la búsqueda del sistema global. En términos generales, esta funcionalidad consta de una única interfaz de usuario de todo el sistema que permite a los usuarios ingresar consultas, muestra sugerencias como usuarios tipo y muestra resultados. Las API de Android permiten a los desarrolladores reutilizar esta interfaz para proporcionar una búsqueda dentro de sus propias aplicaciones y permitir a los desarrolladores proporcionar resultados a la interfaz de usuario de búsqueda global común.

Las implementaciones de dispositivos Android deben incluir Global Search, una interfaz de usuario de búsqueda única, compartida y en todo el sistema, capaz de sugerencias en tiempo real en respuesta a la entrada del usuario. Las implementaciones de dispositivos deben implementar las API que permiten a los desarrolladores reutilizar esta interfaz de usuario para proporcionar una búsqueda dentro de sus propias aplicaciones. Las implementaciones de dispositivos que implementan la interfaz de búsqueda global deben implementar las API que permitan a las aplicaciones de terceros agregar sugerencias al cuadro de búsqueda cuando se ejecuta en modo de búsqueda global. Si no se instalan aplicaciones de terceros que utilizan esta funcionalidad, el comportamiento predeterminado debe ser mostrar los resultados y sugerencias del motor de búsqueda web.

Las implementaciones del dispositivo Android deben implementar un asistente en el dispositivo para manejar la acción de asistencia [ recursos, 30 ].

Android también incluye las API de asistencia para permitir que las aplicaciones elijan cuánta información del contexto actual se comparte con el Asistente en el dispositivo [ Recursos, 31 ]. Las implementaciones de dispositivos que admiten la acción de asistencia deben indicar claramente al usuario final cuando el contexto se comparte mostrando una luz blanca alrededor de los bordes de la pantalla. Para garantizar una visibilidad clara para el usuario final, la indicación debe cumplir o superar la duración y el brillo de la implementación del proyecto de código abierto de Android.

3.8.5. Brindis

Las aplicaciones pueden usar la API de "tostadas" para mostrar cadenas no modales cortas al usuario final, que desaparecen después de un breve período de tiempo [ recursos, 32 ]. Las implementaciones de dispositivos deben mostrar tostadas de aplicaciones a usuarios finales de una manera de alta visibilidad.

3.8.6. Temas

Android proporciona "temas" como mecanismo para que las aplicaciones apliquen estilos en toda una actividad o aplicación.

Android incluye una familia de temas "holo" como un conjunto de estilos definidos para que los desarrolladores de aplicaciones lo usen si quieren que coincidan con el aspecto del tema de Holo y la sensación definida por el SDK de Android [ Recursos, 33 ]. Las implementaciones de dispositivos no deben alterar ninguno de los atributos del tema de Holo expuestos a las aplicaciones [ recursos, 34 ].

Android incluye una familia de temas de "material" como un conjunto de estilos definidos para que los desarrolladores de aplicaciones lo usen si desean coincidir con la apariencia del tema del diseño en la amplia variedad de diferentes tipos de dispositivos Android. Las implementaciones de dispositivos deben admitir la familia de temas "material" y no deben alterar ninguno de los atributos del tema del material o sus activos expuestos a aplicaciones [ recursos, 35 ].

Android también incluye una familia de temas de "dispositivo predeterminado del dispositivo" como un conjunto de estilos definidos para que los desarrolladores de aplicaciones usen si desean coincidir con el aspecto del tema del dispositivo según lo definido por el implementador del dispositivo. Las implementaciones del dispositivo pueden modificar los atributos del tema predeterminados del dispositivo expuestos a las aplicaciones [ recursos, 34 ].

Android admite un tema variante con barras de sistema translúcido, que permite a los desarrolladores de aplicaciones llenar el área detrás del estado y la barra de navegación con el contenido de su aplicación. Para habilitar una experiencia de desarrollador consistente en esta configuración, es importante que el estilo de icono de la barra de estado se mantenga en diferentes implementaciones de dispositivos. Por lo tanto, las implementaciones de dispositivos Android deben usar blancos para los iconos de estado del sistema (como la intensidad de la señal y el nivel de la batería) y las notificaciones emitidas por el sistema, a menos que el icono indique un estado problemático o una aplicación solicite una barra de estado de luz utilizando el sistema System_UI_FLAG_STATUS_BAR. Cuando una aplicación solicita una barra de estado de luz, las implementaciones de dispositivos de Android deben cambiar el color de los iconos de estado del sistema a negros [ recursos, 34 ].

3.8.7. Fondos de pantalla vivos

Android define un tipo de componente y la API y el ciclo de vida correspondiente que permite que las aplicaciones expongan uno o más "fondos de pantalla en vivo" al usuario final [ recursos, 36 ]. Los fondos de pantalla en vivo son animaciones, patrones o imágenes similares con capacidades de entrada limitadas que se muestran como fondo de pantalla, detrás de otras aplicaciones.

El hardware se considera capaz de ejecutar fondos de pantalla en vivo de manera confiable si puede ejecutar todos los fondos de pantalla en vivo, sin limitaciones en la funcionalidad, a una velocidad de fotogramas razonable sin efectos adversos en otras aplicaciones. Si las limitaciones en el hardware hacen que los fondos de pantalla y/o las aplicaciones se bloqueen, funcionen mal, consumen una CPU excesiva o energía de la batería, o se ejecute a velocidades de cuadro inaceptablemente bajas, el hardware se considera incapaz de ejecutar papel tapiz vivo. Como ejemplo, algunos fondos de pantalla en vivo pueden usar un contexto OpenGL 2.0 o 3.x para representar su contenido. Live Wallpaper no se ejecutará de manera confiable en hardware que no admite múltiples contextos OpenGL porque el uso de papel tapiz en vivo de un contexto OpenGL puede entrar en conflicto con otras aplicaciones que también usan un contexto OpenGL.

Implementaciones de dispositivos capaces de ejecutar fondos de pantalla en vivo de manera confiable como se describe anteriormente debe implementar fondos de pantalla en vivo, y cuando se implementan deben informar la función de la plataforma flag.software.live_wallpaper.

3.8.8. Cambio de actividad

El código fuente de Android ascendente incluye la pantalla de descripción general [ recursos, 37 ], una interfaz de usuario a nivel de sistema para el cambio de tareas y la visualización de actividades y tareas recientemente accedidas utilizando una imagen en miniatura del estado gráfico de la aplicación en el momento en que el usuario dejó la aplicación. Las implementaciones de dispositivos, incluida la clave de navegación de la función reciente, como se detalla en la Sección 7.2.3 , pueden alterar la interfaz, pero deben cumplir con los siguientes requisitos:

• Debe mostrar los recientes afiliados como un grupo que se mueve juntos.
• Debe admitir al menos hasta 6 actividades mostradas.
• Debería al menos mostrar el título de 4 actividades a la vez.
• Debe mostrar resaltar color, icono, título de pantalla en recientes.
• Debe implementar el comportamiento de fijación de pantalla [ recursos, 38 ] y proporcionar al usuario un menú de configuración para alternar la función.
• Debe mostrar una posibilidad de cierre ("x"), pero puede retrasar esto hasta que el usuario interactúe con las pantallas.

Las implementaciones de dispositivos se recomiendan encarecidamente para usar la interfaz de usuario de Android ascendente (o una interfaz de miniatura similar) para la pantalla de descripción general.

3.8.9. Gestión de entradas

Android incluye soporte para la gestión de entrada y soporte para editores de métodos de entrada de terceros [ recursos, 39 ]. Las implementaciones de dispositivos que permiten a los usuarios usar métodos de entrada de terceros en el dispositivo deben declarar la función de la plataforma android.software.input_methods y admitir API IME según lo definido en la documentación SDK de Android.

Las implementaciones de dispositivos que declaran la función Android.software.input_methods deben proporcionar un mecanismo accesible para el usuario para agregar y configurar métodos de entrada de terceros. Las implementaciones del dispositivo deben mostrar la interfaz de configuración en respuesta a Android.settings.Input_method_settings Intent.

3.8.10. Bloquear el control de medios de pantalla

La API del cliente de control remoto está en desuso de Android 5.0 a favor de la plantilla de notificación de medios que permite que las aplicaciones de medios se integren con los controles de reproducción que se muestran en la pantalla de bloqueo [ recursos, 40 ] como notificaciones de pantalla de bloqueo. Las implementaciones del dispositivo deben representar la plantilla de notificación de medios correctamente como parte de las notificaciones de la pantalla de bloqueo descritas en la Sección 3.8.3.

3.8.11. Sueños

Android incluye soporte para capturas de pantalla interactiva llamada Dreams [ Resources, 41 ]. Dreams permite a los usuarios interactuar con aplicaciones cuando un dispositivo conectado a una fuente de alimentación está inactiva o acoplada en un muelle de escritorio. Los dispositivos de reloj de Android pueden implementar sueños, pero otros tipos de implementaciones de dispositivos deben incluir soporte para sueños y proporcionar una opción de configuración para que los usuarios configuren sueños en respuesta a Android.settings.Dream_Settings Intent.

3.8.12. Ubicación

Cuando un dispositivo tiene un sensor de hardware (por ejemplo, GPS) que es capaz de proporcionar las coordenadas de ubicación, los modos de ubicación deben mostrarse en el menú de ubicación dentro de la configuración [ Recursos, 42 ].

3.8.13. Unicode y fuente

Android incluye soporte para caracteres de emoji de color. Cuando las implementaciones del dispositivo Android incluyen un IME, los dispositivos deben proporcionar un método de entrada al usuario para los caracteres emoji definidos en Unicode 6.1 [ Recursos, 43 ]. Todos los dispositivos deben ser capaces de representar estos caracteres emoji en el glifo de color.

Android incluye soporte para la fuente Roboto 2 con diferentes pesos: sans-serif-fin, sans-serif-light, sans-serif-medium, sans-serif-newning, sans-serif, acondicionado, sans-serif-condensado con luz, que Todos deben incluirse para los idiomas disponibles en el dispositivo y la cobertura completa de Unicode 7.0 de latín, griego y cirílico, incluido el latín extendido A, B, C y D rangos, y todos los glifos en el bloque de símbolos de divisas de Unicode 7.0.

3.9. Administración de dispositivos

Android incluye características que permiten que las aplicaciones conscientes de la seguridad realicen funciones de administración de dispositivos a nivel del sistema, como hacer cumplir las políticas de contraseña o realizar una limpieza remota, a través de la API de administración de dispositivos de Android [ recursos, 44 ]. Las implementaciones de dispositivos deben proporcionar una implementación de la clase DevicePolicyManager [ recursos, 45 ]. Las implementaciones de dispositivos que incluyen soporte para pantallas de bloqueo PIN (numéricas) o contraseñas (alfanuméricas) deben admitir la gama completa de políticas de administración de dispositivos definidas en la documentación SDK de Android [ recursos, 44 ] e informar la función de plataforma android.software.device_admin.

3.9.1 Aprovisionamiento de dispositivos

3.9.1.1 Aprovisionamiento del propietario del dispositivo

Si una implementación de un dispositivo declara la función Android.software.device_admin, el flujo de configuración fuera de caja debe hacer posible inscribir una aplicación de controlador de políticas de dispositivo (DPC) como la aplicación del propietario del dispositivo [ recursos, 46 ]. Las implementaciones de dispositivos pueden tener una aplicación preinstalada que realiza funciones de administración de dispositivos, pero esta aplicación no debe configurarse como la aplicación del propietario del dispositivo sin consentimiento o acción explícita del usuario o el administrador del dispositivo.

El proceso de aprovisionamiento del propietario del dispositivo (el flujo iniciado por android.app.action.provision_managed_device [ recursos, 47 ]) La experiencia del usuario debe alinearse con la implementación de AOSP

Si la implementación del dispositivo informa android.hardware.nfc, debe tener NFC habilitado, incluso durante el flujo de configuración fuera de caja, para permitir el aprovisionamiento de NFC de los propietarios de dispositivos [ recursos, 48 ].

3.9.1.2 Aprovisionamiento de perfil administrado

Si una implementación de un dispositivo declara el android.software.managed_users, debe ser posible inscribir una aplicación de controlador de políticas de dispositivo (DPC) como propietario de un nuevo perfil administrado [ Recursos, 49 ]

El proceso de aprovisionamiento de perfil administrado (el flujo iniciado por android.app.action.provision_managed_profile [ recursos, 50 ]) La experiencia del usuario debe alinearse con la implementación de AOSP

3.9.2 Soporte de perfil administrado

Los dispositivos capaces de perfil administrado son aquellos dispositivos que:

• Declarar android.software.device_admin (consulte la Sección 3.9 Administración de dispositivos)
• No son dispositivos RAM bajos (ver Sección 7.6.1
• Asigne el almacenamiento interno (no removible) como almacenamiento compartido (consulte la Sección 7.6.2 )

Los dispositivos capaces de perfil administrado deben:

• Declare la función de la plataforma Flag Android.software.Manageed_users.
• Soporte de perfiles administrados a través de Android.app.admin.devicepolicyManager API
• Permita que se cree un perfil administrado [ recursos, 50 ]
• Use una insignia de iconos (similar a la insignia de trabajo aguas arriba de AOSP) para representar las aplicaciones y widgets administrados y otros elementos de interfaz de usuario con pestañas como recientes y notificaciones
• Mostrar un icono de notificación (similar a la insignia de trabajo aguas arriba de AOSP) para indicar cuándo el usuario está dentro de una aplicación de perfil administrado
• Mostrar una tostada que indica que el usuario está en el perfil administrado si el dispositivo se despierta (action_user_present) y la aplicación de primer plano está dentro del perfil administrado
• Cuando existe un perfil administrado, muestre una contenido visual en la intención 'Chooser' para permitir al usuario reenviar la intención del perfil administrado al usuario primario o viceversa, si el controlador de políticas de dispositivos lo está habilitada por el dispositivo.
• Cuando exista un perfil administrado, exponga las siguientes posibilidades del usuario tanto para el usuario principal como para el perfil administrado:
  • Contabilidad separada de batería, ubicación, datos móviles y uso de almacenamiento para el usuario principal y el perfil administrado.
  • Gestión independiente de aplicaciones VPN instaladas dentro del usuario primario o perfil administrado.
  • Gestión independiente de aplicaciones instaladas dentro del usuario principal o perfil administrado.
  • Gestión independiente de cuentas dentro del usuario primario o perfil administrado.
• Asegúrese de que el marcador predeterminado pueda buscar la información de la llamada del perfil administrado (si existe) junto con los del perfil primario, si el controlador de política del dispositivo lo permite.
• Debe asegurarse de que satisfaga todos los requisitos de seguridad aplicables para un dispositivo con múltiples usuarios habilitados (consulte la Sección 9.5 ), a pesar de que el perfil administrado no se cuenta como otro usuario además del usuario principal.

3.10. Accesibilidad

Android proporciona una capa de accesibilidad que ayuda a los usuarios con discapacidades a navegar sus dispositivos más fácilmente. Además, Android proporciona API de plataforma que permiten que las implementaciones de servicios de accesibilidad reciban devoluciones de llamada para eventos de usuario y sistema y generen mecanismos de retroalimentación alternativos, como texto a voz, comentarios hápticos y navegación Trackball/D-Pad [ recursos, 51 ].

Las implementaciones del dispositivo incluyen los siguientes requisitos:

• Las implementaciones automotrices de Android deberían proporcionar una implementación del marco de accesibilidad de Android consistente con la implementación predeterminada de Android.
• Las implementaciones de dispositivos (Android Automotive excluida) deben proporcionar una implementación del marco de accesibilidad de Android consistente con la implementación predeterminada de Android.
• Las implementaciones de dispositivos (Android Automotive excluido) deben admitir implementaciones de servicios de accesibilidad de terceros a través de Android .
• Las implementaciones de dispositivos (Android Automotive excluida) deben generar eventos de accesibilidad y entregar estos eventos a todas las implementaciones de servicios de accesibilidad registrados de manera consistente con la implementación predeterminada de Android
• Implementaciones de dispositivos (Android Automotive y Android Watch Devices sin salida de audio excluida), deben proporcionar un mecanismo accesible para el usuario para habilitar y deshabilitar los servicios de accesibilidad, y debe mostrar esta interfaz en respuesta a Android.Provider.Settings.Action_Accessity_Settings Intent.

Además, las implementaciones del dispositivo deben proporcionar una implementación de un servicio de accesibilidad en el dispositivo y deben proporcionar un mecanismo para que los usuarios habiliten el servicio de accesibilidad durante la configuración del dispositivo. Una implementación de código abierto de un servicio de accesibilidad está disponible en el proyecto Free Project [ recursos, 53 ].

3.11. Texto a voz

Android incluye API que permiten que las aplicaciones utilicen servicios de texto a voz (TTS) y permitan a los proveedores de servicios proporcionar implementaciones de TTS Services [ recursos, 54 ]. Implementaciones de dispositivos informando la función Android.hardware.audio.output debe cumplir con estos requisitos relacionados con el marco de Android TTS.

Implementaciones automotrices de Android:

• Debe admitir las API de Android TTS Framework.
• Puede admitir la instalación de motores TTS de terceros. Si se admite, los socios deben proporcionar una interfaz accesible para el usuario que permita al usuario seleccionar un motor TTS para usar a nivel de sistema.

Todas las demás implementaciones del dispositivo:

• Debe admitir las API de Android TTS Framework e incluir un motor TTS que admite los idiomas disponibles en el dispositivo. Tenga en cuenta que el software de código abierto de Android Upstream incluye una implementación de motor TTS con todas las funciones.
• Debe admitir la instalación de motores TTS de terceros
• Debe proporcionar una interfaz accesible para el usuario que permita a los usuarios seleccionar un motor TTS para usar a nivel del sistema

3.12. Marco de entrada de TV

El Android Television Input Framework (TIF) simplifica la entrega de contenido en vivo a dispositivos de televisión Android. TIF proporciona una API estándar para crear módulos de entrada que controlan los dispositivos de televisión Android. Las implementaciones de dispositivos de televisión de Android deben admitir el marco de entrada de TV [ recursos, 55 ].

Implementaciones de dispositivos que admiten TIF deben declarar la función de la plataforma android.software.live_tv.

3.12.1. Aplicación de televisión

Cualquier implementación del dispositivo que declare soporte para TV en vivo debe tener una aplicación de TV instalada (aplicación de TV). El proyecto de código abierto de Android proporciona una implementación de la aplicación TV.

La aplicación TV predeterminada debe proporcionar acceso a canales desde entradas instaladas y entradas de terceros. Tenga en cuenta que las entradas instaladas abarcan todas las entradas proporcionadas por defecto, ya sea que estén basadas en TIF o no.

La aplicación de TV debe proporcionar instalaciones para instalar y usar canales de TV [ recursos, 56 ] y cumplir con los siguientes requisitos:

• Las implementaciones de dispositivos deben permitir que las entradas de terceros basadas en TIF (entradas de terceros) [ recursos, 57 ] se instalen y administren.
• Las implementaciones de dispositivos pueden proporcionar una separación visual entre las entradas preinstaladas basadas en TIF (entradas instaladas) [ recursos, 58 ] y entradas de terceros.
• Las implementaciones del dispositivo no deben mostrar las entradas de terceros más de una sola acción de navegación de la aplicación TV (es decir, ampliar una lista de entradas de terceros de la aplicación TV).

3.12.1.1. Guía de programas electrónicos

Las implementaciones de dispositivos de televisión de Android deben mostrar una superposición informativa e interactiva, que debe incluir una Guía de programa electrónico (EPG) generada a partir de los valores en los campos TVContrams [ recursos, 59 ]. El EPG debe cumplir con los siguientes requisitos:

• El EPG debe mostrar información de todas las entradas instaladas y entradas de terceros.
• El EPG puede proporcionar una separación visual entre las entradas instaladas y las entradas de terceros.
• Se recomienda encarecidamente que la EPG muestre entradas instaladas y entradas de terceros con igual prominencia. El EPG no debe mostrar las entradas de terceros más de una sola acción de navegación lejos de las entradas instaladas en el EPG.
• En el cambio de canal, las implementaciones del dispositivo deben mostrar datos de EPG para el programa de reproducción actualmente.

3.12.1.2. Navegación

Los dispositivos de entrada del dispositivo de televisión Android (es decir, control remoto, aplicación de control remoto o controlador de juego) deben permitir la navegación a todas las secciones procesables de la pantalla a través del D-PAD. D-Pad arriba y abajo debe usarse para cambiar los canales de TV en vivo cuando no hay una sección procesable en la pantalla.

La aplicación TV debe pasar eventos clave a las entradas HDMI a través de CEC.

3.12.1.3. Enlace de la aplicación de entrada de TV

Las implementaciones de dispositivos de televisión de Android deben admitir el enlace de la aplicación de entrada de TV, lo que permite que todas las entradas proporcionen enlaces de actividad desde la actividad actual a otra actividad (es decir, un enlace desde la programación en vivo hasta el contenido relacionado) [ Recursos, 60 ]. La aplicación de TV debe mostrar la aplicación de entrada de TV cuando se proporcione.

4. Compatibilidad de envasado de aplicaciones

Las implementaciones de dispositivos deben instalar y ejecutar archivos Android ".APK" según lo generado por la herramienta "AAPT" incluida en el SDK oficial de Android [ recursos, 61 ].

Las implementaciones de dispositivos no deben extender el .apk [ recursos, 62 ], Android manifiest [ recursos, 49 ], dalvik bytecode [ recursos, 23 ] o formatos de bytecode rendererscript de tal manera que eviten que esos archivos se instalen y se ejecuten correctamente Otros dispositivos compatibles.

5. Compatibilidad multimedia

5.1. Códecs de medios

Las implementaciones de dispositivos deben admitir los formatos de medios centrales especificados en la documentación SDK de Android [ recursos, 64 ] excepto cuando se permitan explícitamente en este documento. Específicamente, las implementaciones de dispositivos deben admitir los formatos de medios, codificadores, decodificadores, tipos de archivos y formatos de contenedores definidos en las tablas a continuación e informados a través de MediaCodeClist [ recursos, 65 ]. Las implementaciones de dispositivos también deben poder decodificar todos los perfiles informados en su CamcorderProfile [ recursos, 66 ] y deben poder decodificar todos los formatos que puede codificar. Todos estos códecs se proporcionan como implementaciones de software en la implementación de Android preferida del proyecto de código abierto de Android.

Tenga en cuenta que ni Google ni la Alianza de Manso abierto hacen que estos códecs estén libres de patentes de terceros. Aquellos que tienen la intención de usar este código fuente en productos de hardware o software se recomienda que las implementaciones de este código, incluido el software de código abierto o el shareware, pueden requerir licencias de patentes de los titulares de patentes relevantes.

5.1.1. Códecs de audio

Formato/códec	Codificador	Descifrador	Detalles	Tipos de archivos/formatos de contenedor compatibles
Perfil MPEG-4 AAC (AAC LC)	Requerido 1	REQUERIDO	Soporte para mono/estéreo/5.0/5.1 2 Contenido con tasas de muestreo estándar de 8 a 48 kHz.	3GPP (.3gp) MPEG-4 (.mp4, .m4a) ADTS RAW AAC (.AAC, decodifica en Android 3.1+, codifica en Android 4.0+, ADIF no es compatible) MPEG-TS (.ts, no solicitable, Android 3.0+)
MPEG-4 HE AAC Perfil (AAC+)	Requerido 1 (Android 4.1+)	REQUERIDO	Soporte para mono/estéreo/5.0/5.1 2 Contenido con tasas de muestreo estándar de 16 a 48 kHz.
Mpeg-4 él aacv2 Perfil (AAC+mejorado)		REQUERIDO	Soporte para mono/estéreo/5.0/5.1 2 Contenido con tasas de muestreo estándar de 16 a 48 kHz.
AAC ELD (AAC de baja retraso mejorado)	Requerido 1 (Android 4.1+)	REQUERIDO (Android 4.1+)	Soporte para contenido mono/estéreo con tasas de muestreo estándar de 16 a 48 kHz.
AMR-NB	Requerido 3	Requerido 3	4.75 a 12.2 kbps muestreados a 8 kHz	3GPP (.3gp)
AMR-WB	Requerido 3	Requerido 3	9 tasas de 6.60 kbit/s a 23.85 kbit/s muestreadas @ 16 kHz
FLAC		REQUERIDO (Android 3.1+)	Mono/estéreo (sin multicanal). Las velocidades de muestra de hasta 48 kHz (pero hasta 44.1 kHz se recomiendan en dispositivos con salida de 44.1 kHz, ya que el de 44.1 kHz descendente no incluye un filtro de paso bajo). Recomendado de 16 bits; No se aplicó a Dither para 24 bits.	FLAC (.flac) solo
MP3		REQUERIDO	Mono/estéreo 8-320kbps constante (CBR) o tasa de bits variable (VBR)	MP3 (.mp3)
midi		REQUERIDO	MIDI Tipo 0 y 1. DLS versión 1 y 2. XMF y Mobile XMF. Soporte para formatos de tono de llamada RTTTL/RTX, OTA e Imelody	Tipo 0 y 1 (.mid, .xmf, .mxmf) Rtttl/rtx (.rtttl, .rtx) OTA (.ota) Imelody (.imy)
Vorbis		REQUERIDO		OGG (.OGG) Matroska (.mkv, Android 4.0+)
PCM/OVE	Requerido 4 (Android 4.1+)	REQUERIDO	PCM lineal de 16 bits (tasas hasta el límite del hardware). Los dispositivos deben admitir las tasas de muestreo para el registro de PCM sin procesar a las frecuencias de 8000, 11025, 16000 y 44100 Hz.	Ola (.wav)
Opus		REQUERIDO (Android 5.0+)		Matroska (.mkv)

1 Requerido para implementaciones de dispositivos que definan Android.hardware.microphone pero opcional para las implementaciones de dispositivos de reloj de Android.

2 Solo se requiere mezcla descendente del contenido 5.0/5.1; La grabación o la representación de más de 2 canales es opcional.

3 Requerido para implementaciones de dispositivos de mano Android.

4 Requerido para implementaciones de dispositivos que definen Android.hardware.Microphone, incluidas las implementaciones de dispositivos de relojes Android.

5.1.2. Códecos de imagen

Formato/códec	Codificador	Descifrador	Detalles	Tipos de archivos/formatos de contenedor compatibles
JPEG	REQUERIDO	REQUERIDO	Base+progresivo	JPEG (.jpg)
GIF		REQUERIDO		GIF (.gif)
PNG	REQUERIDO	REQUERIDO		PNG (.png)
BMP		REQUERIDO		BMP (.BMP)
WebP	REQUERIDO	REQUERIDO		Webp (.webp)

5.1.3. Códecs de vídeo

Formato/códec	Codificador	Descifrador	Detalles	Tipos de archivos compatibles/ Formatos de contenedor
H.263	Requerido 1	Requerido 2		3GPP (.3gp) MPEG-4 (.mp4)
H.264 AVC	Requerido 2	Requerido 2	Consulte la Sección 5.2 y 5.3 para más detalles	3GPP (.3gp) MPEG-4 (.mp4) MPEG-2 TS (.ts, AAC Audio solamente, no solicitable, Android 3.0+)
H.265 HEVC		Requerido 5	Consulte la Sección 5.3 para más detalles	MPEG-4 (.mp4)
MPEG-2		Muy recomendable 6	Perfil principal	MPEG2-TS
MPEG-4 SP		Requerido 2		3GPP (.3gp)
VP8 3	Requerido 2 (Android 4.3+)	Requerido 2 (Android 2.3.3+)	Consulte la Sección 5.2 y 5.3 para más detalles	Webm (.webm) [ recursos, 67 Matroska (.mkv, Android 4.0+) 4
VP9		Requerido 2 (Android 4.4+)	Consulte la Sección 5.3 para más detalles	Webm (.webm) [ recursos, 67 ] Matroska (.mkv, Android 4.0+) 4

1 requerido para implementaciones de dispositivos que incluyen hardware de cámara y definen android.hardware.camera o android.hardware.camera.front.

2 Requerido para implementaciones de dispositivos, excepto los dispositivos de reloj de Android.

3 Para la calidad aceptable de la transmisión de video web y los servicios de videoconferencia, las implementaciones de dispositivos deben usar un códec VP8 de hardware que cumpla con los requisitos en [ Recursos, 68 ].

4 Implementaciones de dispositivos deben admitir la escritura de archivos Webm de Matroska.

5 Muy recomendable para el automóvil Android, opcional para el reloj Android y requerido para todos los demás tipos de dispositivos.

6 se aplica solo a las implementaciones de dispositivos de televisión de Android.

5.2. Codificación de vídeo

Implementaciones de dispositivos Android con codificadores H.263, deben admitir el nivel de perfil de línea de base 45.

Implementaciones de dispositivos Android con soporte de códec H.264, debe admitir el nivel de perfil de línea de base Nivel 3 y los siguientes perfiles de codificación de video SD (definición estándar) y deben admitir el nivel de perfil principal 4 y los siguientes perfiles de codificación de video HD (alta definición). Se recomienda encarecidamente que los dispositivos de televisión de Android codifiquen el video HD 1080p a 30 fps.

	SD (baja calidad)	SD (alta calidad)	HD 720P 1	HD 1080P 1
Resolución de video	320 x 240 píxeles	720 x 480 PX	1280 x 720 píxeles	1920 x 1080 píxeles
Velocidad de fotogramas de vídeo	20 fps	30 fps	30 fps	30 fps
Bitrate de vídeo	384 kbps	2Mbps	4Mbps	10Mbps

1 cuando es compatible con el hardware, pero es muy recomendable para dispositivos de televisión Android.

Android device implementations with VP8 codec support MUST support the SD video encoding profiles and SHOULD support the following HD (High Definition) video encoding profiles.

	SD (Low quality)	SD (High quality)	HD 720p 1	HD 1080p 1
Resolución de video	320 x 180 px	640 x 360 px	1280 x 720 píxeles	1920 x 1080 píxeles
Velocidad de fotogramas de vídeo	30 fps	30 fps	30 fps	30 fps
Bitrate de vídeo	800 kbps	2Mbps	4Mbps	10Mbps

1 When supported by hardware.

5.3. Decodificación de vídeo

Device implementations MUST support dynamic video resolution and frame rate switching through the standard Android APIs within the same stream for all VP8, VP9, H.264, and H.265 codecs in real time and up to the maximum resolution supported by each codec on the dispositivo.

Android device implementations with H.263 decoders, MUST support Baseline Profile Level 30.

Android device implementations with MPEG-4 decoders, MUST support Simple Profile Level 3.

Android device implementations with H.264 decoders, MUST support Main Profile Level 3.1 and the following SD video decoding profiles and SHOULD support the HD decoding profiles. Android Television devices MUST support High Profile Level 4.2 and the HD 1080p decoding profile.

	SD (Low quality)	SD (High quality)	HD 720p 1	HD 1080p 1
Resolución de video	320 x 240 píxeles	720 x 480 px	1280 x 720 píxeles	1920 x 1080 píxeles
Velocidad de fotogramas de vídeo	30 fps	30 fps	60 fps	30 fps / 60 fps 2
Bitrate de vídeo	800 kbps	2Mbps	8Mbps	20Mbps

1 REQUIRED for when the height as reported by the Display.getSupportedModes() method is equal or greater than the video resolution.

2 REQUIRED for Android Television device implementations.

Android device implementations when supporting VP8 codec as described in section 5.1.3 , MUST support the following SD decoding profiles and SHOULD support the HD decoding profiles. Android Television devices MUST support the HD 1080p decoding profile.

	SD (Low quality)	SD (High quality)	HD 720p 1	HD 1080p 1
Resolución de video	320 x 180 px	640 x 360 px	1280 x 720 píxeles	1920 x 1080 píxeles
Velocidad de fotogramas de vídeo	30 fps	30 fps	30 fps / 60 fps 2	30 / 60 fps 2
Bitrate de vídeo	800 kbps	2Mbps	8Mbps	20Mbps

1 REQUIRED for when the height as reported by the Display.getSupportedModes() method is equal or greater than the video resolution.

2 REQUIRED for Android Television device implementations.

Android device implementations, when supporting VP9 codec as described in section 5.1.3 , MUST support the following SD video decoding profiles and SHOULD support the HD decoding profiles. Android Television devices are STRONGLY RECOMMENDED to support the HD 1080p decoding profile and SHOULD support the UHD decoding profile. When the UHD video decoding profile is supported, it MUST support 8-bit color depth and SHOULD support VP9 Profile 2 (10-bit).

	SD (Low quality)	SD (High quality)	HD 720p 1	HD 1080p 2	UHD 2
Resolución de video	320 x 180 px	640 x 360 px	1280 x 720 píxeles	1920 x 1080 píxeles	3840 x 2160 píxeles
Velocidad de fotogramas de vídeo	30 fps	30 fps	30 fps	60 fps	60 fps
Bitrate de vídeo	600 Kbps	1.6 Mbps	4Mbps	5Mbps	20Mbps

1 Required for Android Television device implementations, but for other type of devices only when supported by hardware.

2 STRONGLY RECOMMENDED for existing Android Television device implementations when supported by hardware.

Android device implementations, when supporting H.265 codec as described in section 5.1.3 , MUST support the Main Profile Level 3 Main tier and the following SD video decoding profiles and SHOULD support the HD decoding profiles. Android Television devices are STRONGLY RECOMMENDED to support the UHD decoding profile and the HD 1080p decoding profile. If the HD 1080p decoding profile is supported, it MUST support the Main Profile Level 4.1 Main tier. If UHD decoding is supported, then it MUST support Main10 Level 5 Main Tier profile.

	SD (Low quality)	SD (High quality)	HD 720p 1	HD 1080p 2	UHD 2
Resolución de video	352 x 288 px	640 x 360 px	1280 x 720 píxeles	1920 x 1080 píxeles	3840 x 2160 píxeles
Velocidad de fotogramas de vídeo	30 fps	30 fps	30 fps	60 fps 2	60 fps
Bitrate de vídeo	600 Kbps	1.6 Mbps	4Mbps	10Mbps	20Mbps

1 Required for Android Television device implementations, but for other type of devices only when supported by hardware.

2 STRONGLY RECOMMENDED for existing Android Television device implementations when supported by hardware.

5.4. Grabación de audio

While some of the requirements outlined in this section are stated as SHOULD since Android 4.3, the Compatibility Definition for a future version is planned to change these to MUST. Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements that are stated as SHOULD, or they will not be able to attain Android compatibility when upgraded to the future version.

5.4.1. Raw Audio Capture

Device implementations that declare android.hardware.microphone MUST allow capture of raw audio content with the following characteristics:

• Format : Linear PCM, 16-bit
• Sampling rates : 8000, 11025, 16000, 44100
• Channels : Mono

The capture for the above sample rates MUST be done without up-sampling, and any down-sampling MUST include an appropriate anti-aliasing filter.

Device implementations that declare android.hardware.microphone SHOULD allow capture of raw audio content with the following characteristics:

• Format : Linear PCM, 16-bit
• Sampling rates : 22050, 48000
• Canales : Estéreo

If capture for the above sample rates is supported, then the capture MUST be done without up-sampling at any ratio higher than 16000:22050 or 44100:48000. Any up-sampling or down-sampling MUST include an appropriate anti-aliasing filter.

5.4.2. Capture for Voice Recognition

In addition to the above recording specifications, when an application has started recording an audio stream using the android.media.MediaRecorder.AudioSource.VOICE_RECOGNITION audio source:

• The device SHOULD exhibit approximately flat amplitude versus frequency characteristics: specifically, ±3 dB, from 100 Hz to 4000 Hz.
• Audio input sensitivity SHOULD be set such that a 90 dB sound power level (SPL) source at 1000 Hz yields RMS of 2500 for 16-bit samples.
• PCM amplitude levels SHOULD linearly track input SPL changes over at least a 30 dB range from -18 dB to +12 dB re 90 dB SPL at the microphone.
• Total harmonic distortion SHOULD be less than 1% for 1 kHz at 90 dB SPL input level at the microphone.
• Noise reduction processing, if present, MUST be disabled.
• Automatic gain control, if present, MUST be disabled

If the platform supports noise suppression technologies tuned for speech recognition, the effect MUST be controllable from the android.media.audiofx.NoiseSuppressor API. Moreover, the UUID field for the noise suppressor's effect descriptor MUST uniquely identify each implementation of the noise suppression technology.

5.4.3. Capture for Rerouting of Playback

The android.media.MediaRecorder.AudioSource class includes the REMOTE_SUBMIX audio source. Devices that declare android.hardware.audio.output MUST properly implement the REMOTE_SUBMIX audio source so that when an application uses the android.media.AudioRecord API to record from this audio source, it can capture a mix of all audio streams except for the following :

• STREAM_RING
• STREAM_ALARM
• STREAM_NOTIFICATION

5.5. Reproducción de audio

Device implementations that declare android.hardware.audio.output MUST conform to the requirements in this section.

5.5.1. Raw Audio Playback

The device MUST allow playback of raw audio content with the following characteristics:

• Format : Linear PCM, 16-bit
• Sampling rates : 8000, 11025, 16000, 22050, 32000, 44100
• Channels : Mono, Stereo

The device SHOULD allow playback of raw audio content with the following characteristics:

• Sampling rates : 24000, 48000

5.5.2. Efectos de audio

Android provides an API for audio effects for device implementations [ Resources, 69 ]. Device implementations that declare the feature android.hardware.audio.output:

• MUST support the EFFECT_TYPE_EQUALIZER and EFFECT_TYPE_LOUDNESS_ENHANCER implementations controllable through the AudioEffect subclasses Equalizer, LoudnessEnhancer.
• MUST support the visualizer API implementation, controllable through the Visualizer class.
• SHOULD support the EFFECT_TYPE_BASS_BOOST, EFFECT_TYPE_ENV_REVERB, EFFECT_TYPE_PRESET_REVERB, and EFFECT_TYPE_VIRTUALIZER implementations controllable through the AudioEffect sub-classes BassBoost, EnvironmentalReverb, PresetReverb, and Virtualizer.

5.5.3. Audio Output Volume

Android Television device implementations MUST include support for system Master Volume and digital audio output volume attenuation on supported outputs, except for compressed audio passthrough output (where no audio decoding is done on the device).

5.6. Latencia de audio

Audio latency is the time delay as an audio signal passes through a system. Many classes of applications rely on short latencies, to achieve real-time sound effects.

For the purposes of this section, use the following definitions:

• output latency . The interval between when an application writes a frame of PCM-coded data and when the corresponding sound can be heard by an external listener or observed by a transducer.
• cold output latency . The output latency for the first frame, when the audio output system has been idle and powered down prior to the request.
• continuous output latency . The output latency for subsequent frames, after the device is playing audio.
• input latency . The interval between when an external sound is presented to the device and when an application reads the corresponding frame of PCM-coded data.
• cold input latency . The sum of lost input time and the input latency for the first frame, when the audio input system has been idle and powered down prior to the request.
• continuous input latency . The input latency for subsequent frames, while the device is capturing audio.
• cold output jitter . The variance among separate measurements of cold output latency values.
• cold input jitter . The variance among separate measurements of cold input latency values.
• continuous round-trip latency . The sum of continuous input latency plus continuous output latency plus one buffer period. The buffer period term allows processing time for the app and for the app to mitigate phase difference between input and output streams.
• OpenSL ES PCM buffer queue API . The set of PCM-related OpenSL ES APIs within Android NDK; see NDK_root/docs/opensles/index.html.

Device implementations that declare android.hardware.audio.output are STRONGLY RECOMMENDED to meet or exceed these audio output requirements:

• cold output latency of 100 milliseconds or less
• continuous output latency of 45 milliseconds or less
• minimize the cold output jitter

If a device implementation meets the requirements of this section after any initial calibration when using the OpenSL ES PCM buffer queue API, for continuous output latency and cold output latency over at least one supported audio output device, it is STRONGLY RECOMMENDED to report support for low-latency audio, by reporting the feature android.hardware.audio.low_latency via the android.content.pm.PackageManager class [ Resources, 70 ]. Conversely, if the device implementation does not meet these requirements it MUST NOT report support for low-latency audio.

Device implementations that include android.hardware.microphone are STRONGLY RECOMMENDED to meet these input audio requirements:

• cold input latency of 100 milliseconds or less
• continuous input latency of 30 milliseconds or less
• continuous round-trip latency of 50 milliseconds or less
• minimize the cold input jitter

5.7. Protocolos de red

Devices MUST support the media network protocols for audio and video playback as specified in the Android SDK documentation [ Resources, 64 ]. Specifically, devices MUST support the following media network protocols:

• RTSP (RTP, SDP)
• HTTP(S) progressive streaming
• HTTP(S) Live Streaming draft protocol, Version 3 [ Resources, 71 ]

5.8. Medios seguros

Device implementations that support secure video output and are capable of supporting secure surfaces MUST declare support for Display.FLAG_SECURE. Device implementations that declare support for Display.FLAG_SECURE, if they support a wireless display protocol, MUST secure the link with a cryptographically strong mechanism such as HDCP 2.x or higher for Miracast wireless displays. Similarly if they support a wired external display, the device implementations MUST support HDCP 1.2 or higher. Android Television device implementations MUST support HDCP 2.2 for devices supporting 4K resolution and HDCP 1.4 or above for lower resolutions. The upstream Android open source implementation includes support for wireless (Miracast) and wired (HDMI) displays that satisfies this requirement.

5.9. Interfaz digital para instrumentos musicales (MIDI)

If a device implementation supports the inter-app MIDI software transport (virtual MIDI devices), and it supports MIDI over all of the following MIDI-capable hardware transports for which it provides generic non-MIDI connectivity, it is STRONGLY RECOMMENDED to report support for feature android.software.midi via the android.content.pm.PackageManager class [ Resources, 70 ].

The MIDI-capable hardware transports are:

• USB host mode (section 7.7 USB)
• USB peripheral mode (section 7.7 USB)

Conversely, if the device implementation provides generic non-MIDI connectivity over a particular MIDI-capable hardware transport listed above, but does not support MIDI over that hardware transport, it MUST NOT report support for feature android.software.midi.

MIDI over Bluetooth LE acting in central role (section 7.4.3 Bluetooth) is in trial use status. A device implementation that reports feature android.software.midi, and which provides generic non-MIDI connectivity over Bluetooth LE, SHOULD support MIDI over Bluetooth LE.

5.10. Audio profesional

If a device implementation meets all of the following requirements, it is STRONGLY RECOMMENDED to report support for feature android.hardware.audio.pro via the android.content.pm.PackageManager class [ Resources, 70 ].

• The device implementation MUST report support for feature android.hardware.audio.low_latency.
• The continuous round-trip audio latency, as defined in section 5.6 Audio Latency, MUST be 20 milliseconds or less and SHOULD be 10 milliseconds or less over at least one supported path.
• If the device includes a 4 conductor 3.5mm audio jack, the continuous round-trip audio latency MUST be 20 milliseconds or less over the audio jack path, and SHOULD be 10 milliseconds or less over the audio jack path.
• The device implementation MUST include a USB port(s) supporting USB host mode and USB peripheral mode.
• The USB host mode MUST implement the USB audio class.
• If the device includes an HDMI port, the device implementation MUST support output in stereo and eight channels at 20-bit or 24-bit depth and 192 kHz without bit-depth loss or resampling.
• The device implementation MUST report support for feature android.software.midi.
• If the device includes a 4 conductor 3.5mm audio jack, the device implementation is STRONGLY RECOMMENDED to comply with section Mobile device (jack) specifications of the Wired Audio Headset Specification (v1.1) .

6. Developer Tools and Options Compatibility

6.1. Herramientas de desarrollo

Device implementations MUST support the Android Developer Tools provided in the Android SDK. Android compatible devices MUST be compatible with:

• Android Debug Bridge (adb) [ Resources, 72 ]

Device implementations MUST support all adb functions as documented in the Android SDK including dumpsys [ Resources, 73 ]. The device-side adb daemon MUST be inactive by default and there MUST be a user-accessible mechanism to turn on the Android Debug Bridge. If a device implementation omits USB peripheral mode, it MUST implement the Android Debug Bridge via local-area network (such as Ethernet or 802.11).

Android includes support for secure adb. Secure adb enables adb on known authenticated hosts. Device implementations MUST support secure adb.

• Dalvik Debug Monitor Service (ddms) [ Resources, 74 ]

Device implementations MUST support all ddms features as documented in the Android SDK. As ddms uses adb, support for ddms SHOULD be inactive by default, but MUST be supported whenever the user has activated the Android Debug Bridge, as above.

• Monkey [ Resources, 75 ]

Device implementations MUST include the Monkey framework, and make it available for applications to use.

• SysTrace [ Resources, 76 ]

Device implementations MUST support systrace tool as documented in the Android SDK. Systrace must be inactive by default, and there MUST be a user-accessible mechanism to turn on Systrace.

Most Linux-based systems and Apple Macintosh systems recognize Android devices using the standard Android SDK tools, without additional support; however Microsoft Windows systems typically require a driver for new Android devices. (For instance, new vendor IDs and sometimes new device IDs require custom USB drivers for Windows systems.) If a device implementation is unrecognized by the adb tool as provided in the standard Android SDK, device implementers MUST provide Windows drivers allowing developers to connect to the device using the adb protocol. These drivers MUST be provided for Windows XP, Windows Vista, Windows 7, Windows 8 and Windows 10 in both 32-bit and 64-bit versions.

6.2. Opciones de desarrollador

Android includes support for developers to configure application development-related settings. Device implementations MUST honor the android.settings.APPLICATION_DEVELOPMENT_SETTINGS intent to show application development-related settings [ Resources, 77 ]. The upstream Android implementation hides the Developer Options menu by default and enables users to launch Developer Options after pressing seven (7) times on the Settings > About Device > Build Number menu item. Device implementations MUST provide a consistent experience for Developer Options. Specifically, device implementations MUST hide Developer Options by default and MUST provide a mechanism to enable Developer Options that is consistent with the upstream Android implementation.

7. Hardware Compatibility

If a device includes a particular hardware component that has a corresponding API for third-party developers, the device implementation MUST implement that API as described in the Android SDK documentation. If an API in the SDK interacts with a hardware component that is stated to be optional and the device implementation does not possess that component:

• Complete class definitions (as documented by the SDK) for the component APIs MUST still be presented.
• The API's behaviors MUST be implemented as no-ops in some reasonable fashion.
• API methods MUST return null values where permitted by the SDK documentation.
• API methods MUST return no-op implementations of classes where null values are not permitted by the SDK documentation.
• API methods MUST NOT throw exceptions not documented by the SDK documentation.

A typical example of a scenario where these requirements apply is the telephony API: even on non-phone devices, these APIs must be implemented as reasonable no-ops.

Device implementations MUST consistently report accurate hardware configuration information via the getSystemAvailableFeatures() and hasSystemFeature(String) methods on the android.content.pm.PackageManager class for the same build fingerprint. [ Resources, 70 ]

7.1. Pantalla y gráficos

Android includes facilities that automatically adjust application assets and UI layouts appropriately for the device, to ensure that third-party applications run well on a variety of hardware configurations [ Resources, 78 ]. Devices MUST properly implement these APIs and behaviors, as detailed in this section.

The units referenced by the requirements in this section are defined as follows:

• physical diagonal size . The distance in inches between two opposing corners of the illuminated portion of the display.
• dots per inch (dpi) . The number of pixels encompassed by a linear horizontal or vertical span of 1”. Where dpi values are listed, both horizontal and vertical dpi must fall within the range.
• aspect ratio . The ratio of the pixels of the longer dimension to the shorter dimension of the screen. For example, a display of 480x854 pixels would be 854/480 = 1.779, or roughly “16:9”.
• density-independent pixel (dp) The virtual pixel unit normalized to a 160 dpi screen, calculated as: pixels = dps * (density/160).

7.1.1. Configuración de pantalla

7.1.1.1. Tamaño de pantalla

The Android UI framework supports a variety of different screen sizes, and allows applications to query the device screen size (aka “screen layout") via android.content.res.Configuration.screenLayout with the SCREENLAYOUT_SIZE_MASK. Device implementations MUST report the correct screen size as defined in the Android SDK documentation [ Resources, 78 ] and determined by the upstream Android platform. Specifically, device implementations MUST report the correct screen size according to the following logical density-independent pixel (dp) screen dimensions.

• Devices MUST have screen sizes of at least 426 dp x 320 dp ('small'), unless it is an Android Watch device.
• Devices that report screen size 'normal' MUST have screen sizes of at least 480 dp x 320 dp.
• Devices that report screen size 'large' MUST have screen sizes of at least 640 dp x 480 dp.
• Devices that report screen size 'xlarge' MUST have screen sizes of at least 960 dp x 720 dp.

Además,

• Android Watch devices MUST have a screen with the physical diagonal size in the range from 1.1 to 2.5 inches.
• Other types of Android device implementations, with a physically integrated screen, MUST have a screen at least 2.5 inches in physical diagonal size.

Devices MUST NOT change their reported screen size at any time.

Applications optionally indicate which screen sizes they support via the <supports-screens> attribute in the AndroidManifest.xml file. Device implementations MUST correctly honor applications' stated support for small, normal, large, and xlarge screens, as described in the Android SDK documentation.

7.1.1.2. Relación de aspecto de pantalla

The screen aspect ratio MUST be a value from 1.3333 (4:3) to 1.86 (roughly 16:9), but Android Watch devices MAY have an aspect ratio of 1.0 (1:1) because such a device implementation will use a UI_MODE_TYPE_WATCH as the android.content.res.Configuration.uiMode.

7.1.1.3. Densidad de la pantalla

The Android UI framework defines a set of standard logical densities to help application developers target application resources. Device implementations MUST report only one of the following logical Android framework densities through the android.util.DisplayMetrics APIs, and MUST execute applications at this standard density and MUST NOT change the value at at any time for the default display.

• 120 dpi (ldpi)
• 160 dpi (mdpi)
• 213 dpi (tvdpi)
• 240 dpi (hdpi)
• 280 dpi (280dpi)
• 320 dpi (xhdpi)
• 360 dpi (360dpi)
• 400 dpi (400dpi)
• 420 dpi (420dpi)
• 480 dpi (xxhdpi)
• 560 dpi (560dpi)
• 640 dpi (xxxhdpi)

Device implementations SHOULD define the standard Android framework density that is numerically closest to the physical density of the screen, unless that logical density pushes the reported screen size below the minimum supported. If the standard Android framework density that is numerically closest to the physical density results in a screen size that is smaller than the smallest supported compatible screen size (320 dp width), device implementations SHOULD report the next lowest standard Android framework density.

7.1.2. Display Metrics

Device implementations MUST report correct values for all display metrics defined in android.util.DisplayMetrics [ Resources, 79 ] and MUST report the same values regardless of whether the embedded or external screen is used as the default display.

7.1.3. Orientación de la pantalla

Devices MUST report which screen orientations they support (android.hardware.screen.portrait and/or android.hardware.screen.landscape) and MUST report at least one supported orientation. For example, a device with a fixed orientation landscape screen, such as a television or laptop, SHOULD only report android.hardware.screen.landscape.

Devices that report both screen orientations MUST support dynamic orientation by applications to either portrait or landscape screen orientation. That is, the device must respect the application's request for a specific screen orientation. Device implementations MAY select either portrait or landscape orientation as the default.

Devices MUST report the correct value for the device's current orientation, whenever queried via the android.content.res.Configuration.orientation, android.view.Display.getOrientation(), or other APIs.

Devices MUST NOT change the reported screen size or density when changing orientation.

7.1.4. 2D and 3D Graphics Acceleration

Device implementations MUST support both OpenGL ES 1.0 and 2.0, as embodied and detailed in the Android SDK documentations. Device implementations SHOULD support OpenGL ES 3.0 or 3.1 on devices capable of supporting it. Device implementations MUST also support Android RenderScript, as detailed in the Android SDK documentation [ Resources, 80 ].

Device implementations MUST also correctly identify themselves as supporting OpenGL ES 1.0, OpenGL ES 2.0, OpenGL ES 3.0 or OpenGL 3.1. Eso es:

• The managed APIs (such as via the GLES10.getString() method) MUST report support for OpenGL ES 1.0 and OpenGL ES 2.0.
• The native C/C++ OpenGL APIs (APIs available to apps via libGLES_v1CM.so, libGLES_v2.so, or libEGL.so) MUST report support for OpenGL ES 1.0 and OpenGL ES 2.0.
• Device implementations that declare support for OpenGL ES 3.0 or 3.1 MUST support the corresponding managed APIs and include support for native C/C++ APIs. On device implementations that declare support for OpenGL ES 3.0 or 3.1, libGLESv2.so MUST export the corresponding function symbols in addition to the OpenGL ES 2.0 function symbols.

In addition to OpenGL ES 3.1, Android provides an extension pack with Java interfaces [ Resources, 81 ] and native support for advanced graphics functionality such as tessellation and the ASTC texture compression format. Android device implementations MAY support this extension pack, and—only if fully implemented—MUST identify the support through the android.hardware.opengles.aep feature flag.

Also, device implementations MAY implement any desired OpenGL ES extensions. However, device implementations MUST report via the OpenGL ES managed and native APIs all extension strings that they do support, and conversely MUST NOT report extension strings that they do not support.

Note that Android includes support for applications to optionally specify that they require specific OpenGL texture compression formats. These formats are typically vendor-specific. Device implementations are not required by Android to implement any specific texture compression format. However, they SHOULD accurately report any texture compression formats that they do support, via the getString() method in the OpenGL API.

Android includes a mechanism for applications to declare that they want to enable hardware acceleration for 2D graphics at the Application, Activity, Window, or View level through the use of a manifest tag android:hardwareAccelerated or direct API calls [ Resources, 82 ].

Device implementations MUST enable hardware acceleration by default, and MUST disable hardware acceleration if the developer so requests by setting android:hardwareAccelerated="false” or disabling hardware acceleration directly through the Android View APIs.

In addition, device implementations MUST exhibit behavior consistent with the Android SDK documentation on hardware acceleration [ Resources, 82 ].

Android includes a TextureView object that lets developers directly integrate hardware-accelerated OpenGL ES textures as rendering targets in a UI hierarchy. Device implementations MUST support the TextureView API, and MUST exhibit consistent behavior with the upstream Android implementation.

Android includes support for EGL_ANDROID_RECORDABLE, an EGLConfig attribute that indicates whether the EGLConfig supports rendering to an ANativeWindow that records images to a video. Device implementations MUST support EGL_ANDROID_RECORDABLE extension [ Resources, 83 ].

7.1.5. Legacy Application Compatibility Mode

Android specifies a “compatibility mode” in which the framework operates in a 'normal' screen size equivalent (320dp width) mode for the benefit of legacy applications not developed for old versions of Android that pre-date screen-size independence.

• Android Automotive does not support legacy compatibility mode.
• All other device implementations MUST include support for legacy application compatibility mode as implemented by the upstream Android open source code. That is, device implementations MUST NOT alter the triggers or thresholds at which compatibility mode is activated, and MUST NOT alter the behavior of the compatibility mode itself.

7.1.6. Tecnología de pantalla

The Android platform includes APIs that allow applications to render rich graphics to the display. Devices MUST support all of these APIs as defined by the Android SDK unless specifically allowed in this document.

• Devices MUST support displays capable of rendering 16-bit color graphics and SHOULD support displays capable of 24-bit color graphics.
• Devices MUST support displays capable of rendering animations.
• The display technology used MUST have a pixel aspect ratio (PAR) between 0.9 and 1.15. That is, the pixel aspect ratio MUST be near square (1.0) with a 10 ~ 15% tolerance.

7.1.7. Secondary Displays

Android includes support for secondary display to enable media sharing capabilities and developer APIs for accessing external displays. If a device supports an external display either via a wired, wireless, or an embedded additional display connection then the device implementation MUST implement the display manager API as described in the Android SDK documentation [ Resources, 84 ].

7.2. Los dispositivos de entrada

Devices MUST support a touchscreen or meet the requirements listed in 7.2.2 for non-touch navigation.

7.2.1. Teclado

Implementaciones de dispositivos:

• MUST include support for the Input Management Framework (which allows third-party developers to create Input Method Editors—ie soft keyboard) as detailed at http://developer.android.com .
• MUST provide at least one soft keyboard implementation (regardless of whether a hard keyboard is present) except for Android Watch devices where the screen size makes it less reasonable to have a soft keyboard.
• MAY include additional soft keyboard implementations.
• MAY include a hardware keyboard.
• MUST NOT include a hardware keyboard that does not match one of the formats specified in android.content.res.Configuration.keyboard [ Resources, 85 ] (QWERTY or 12-key).

7.2.2. Non-touch Navigation

Implementaciones de dispositivos:

• MAY omit a non-touch navigation option (trackball, d-pad, or wheel) if the device implementation is not an Android Television device.
• MUST report the correct value for android.content.res.Configuration.navigation [ Resources, 85 ].
• MUST provide a reasonable alternative user interface mechanism for the selection and editing of text, compatible with Input Management Engines. The upstream Android open source implementation includes a selection mechanism suitable for use with devices that lack non-touch navigation inputs.

7.2.3. Teclas de navegación

The Home, Recents, and Back functions (mapped to the key events KEYCODE_HOME, KEYCODE_APP_SWITCH, KEYCODE_BACK, respectively) are essential to the Android navigation paradigm and therefore:

• Android Handheld device implementations MUST provide the Home, Recents, and Back functions.
• Android Television device implementations MUST provide the Home and Back functions.
• Android Watch device implementations MUST have the Home function available to the user, and the Back function except for when it is in UI_MODE_TYPE_WATCH.
• Android Automotive implementations MUST provide the Home function and MAY provide Back and Recent functions.
• All other types of device implementations MUST provide the Home and Back functions.

These functions MAY be implemented via dedicated physical buttons (such as mechanical or capacitive touch buttons), or MAY be implemented using dedicated software keys on a distinct portion of the screen, gestures, touch panel, etc. Android supports both implementations. All of these functions MUST be accessible with a single action (eg tap, double-click or gesture) when visible.

Recents function, if provided, MUST have a visible button or icon unless hidden together with other navigation functions in full-screen mode. This does not apply to devices upgrading from earlier Android versions that have physical buttons for navigation and no recents key.

The Home and Back functions, if provided, MUST each have a visible button or icon unless hidden together with other navigation functions in full-screen mode or when the uiMode UI_MODE_TYPE_MASK is set to UI_MODE_TYPE_WATCH.

The Menu function is deprecated in favor of action bar since Android 4.0. Therefore the new device implementations shipping with Android 6.0 and later MUST NOT implement a dedicated physical button for the Menu function. Older device implementations SHOULD NOT implement a dedicated physical button for the Menu function, but if the physical Menu button is implemented and the device is running applications with targetSdkVersion > 10, the device implementation:

• MUST display the action overflow button on the action bar when it is visible and the resulting action overflow menu popup is not empty. For a device implementation launched before Android 4.4 but upgrading to Android 6.0, this is RECOMMENDED.
• MUST NOT modify the position of the action overflow popup displayed by selecting the overflow button in the action bar.
• MAY render the action overflow popup at a modified position on the screen when it is displayed by selecting the physical menu button.

For backwards compatibility, device implementations MUST make the Menu function available to applications when targetSdkVersion is less than 10, either by a physical button, a software key, or gestures. This Menu function should be presented unless hidden together with other navigation functions.

Android device implementations with the support of the Assist action [ Resources, 30 ] MUST make this accessible with a single action (eg tap, double-click, or gesture) when other navigation keys are visible, and are STRONGLY RECOMMENDED to use the long-press on the Home button or software key as the single action.

Device implementations MAY use a distinct portion of the screen to display the navigation keys, but if so, MUST meet these requirements:

• Device implementation navigation keys MUST use a distinct portion of the screen, not available to applications, and MUST NOT obscure or otherwise interfere with the portion of the screen available to applications.
• Device implementations MUST make available a portion of the display to applications that meets the requirements defined in section 7.1.1 .
• Device implementations MUST display the navigation keys when applications do not specify a system UI mode, or specify SYSTEM_UI_FLAG_VISIBLE.
• Device implementations MUST present the navigation keys in an unobtrusive “low profile” (eg. dimmed) mode when applications specify SYSTEM_UI_FLAG_LOW_PROFILE.
• Device implementations MUST hide the navigation keys when applications specify SYSTEM_UI_FLAG_HIDE_NAVIGATION.

7.2.4. Touchscreen Input

Device implementations SHOULD have a pointer input system of some kind (either mouse-like or touch). However, if a device implementation does not support a pointer input system, it MUST NOT report the android.hardware.touchscreen or android.hardware.faketouch feature constant. Device implementations that do include a pointer input system:

• SHOULD support fully independently tracked pointers, if the device input system supports multiple pointers.
• MUST report the value of android.content.res.Configuration.touchscreen [ Resources, 85 ] corresponding to the type of the specific touchscreen on the device.

Android includes support for a variety of touchscreens, touch pads, and fake touch input devices. Touchscreen based device implementations are associated with a display [ Resources, 86 ] such that the user has the impression of directly manipulating items on screen. Since the user is directly touching the screen, the system does not require any additional affordances to indicate the objects being manipulated. In contrast, a fake touch interface provides a user input system that approximates a subset of touchscreen capabilities. For example, a mouse or remote control that drives an on-screen cursor approximates touch, but requires the user to first point or focus then click. Numerous input devices like the mouse, trackpad, gyro-based air mouse, gyro-pointer, joystick, and multi-touch trackpad can support fake touch interactions. Android includes the feature constant android.hardware.faketouch, which corresponds to a high-fidelity non-touch (pointer-based) input device such as a mouse or trackpad that can adequately emulate touch-based input (including basic gesture support), and indicates that the device supports an emulated subset of touchscreen functionality. Device implementations that declare the fake touch feature MUST meet the fake touch requirements in section 7.2.5 .

Device implementations MUST report the correct feature corresponding to the type of input used. Device implementations that include a touchscreen (single-touch or better) MUST report the platform feature constant android.hardware.touchscreen. Device implementations that report the platform feature constant android.hardware.touchscreen MUST also report the platform feature constant android.hardware.faketouch. Device implementations that do not include a touchscreen (and rely on a pointer device only) MUST NOT report any touchscreen feature, and MUST report only android.hardware.faketouch if they meet the fake touch requirements in section 7.2.5 .

7.2.5. Fake Touch Input

Device implementations that declare support for android.hardware.faketouch:

• MUST report the absolute X and Y screen positions of the pointer location and display a visual pointer on the screen [ Resources, 87 ].
• MUST report touch event with the action code that specifies the state change that occurs on the pointer going down or up on the screen [ Resources, 87 ].
• MUST support pointer down and up on an object on the screen, which allows users to emulate tap on an object on the screen.
• MUST support pointer down, pointer up, pointer down then pointer up in the same place on an object on the screen within a time threshold, which allows users to emulate double tap on an object on the screen [ Resources, 87 ].
• MUST support pointer down on an arbitrary point on the screen, pointer move to any other arbitrary point on the screen, followed by a pointer up, which allows users to emulate a touch drag.
• MUST support pointer down then allow users to quickly move the object to a different position on the screen and then pointer up on the screen, which allows users to fling an object on the screen.

Devices that declare support for android.hardware.faketouch.multitouch.distinct MUST meet the requirements for faketouch above, and MUST also support distinct tracking of two or more independent pointer inputs.

7.2.6. Soporte de controlador de juego

Android Television device implementations MUST support button mappings for game controllers as listed below. The upstream Android implementation includes implementation for game controllers that satisfies this requirement.

7.2.6.1. Button Mappings

Android Television device implementations MUST support the following key mappings:

Botón	HID Usage 2	Botón Android
un 1	0x09 0x0001	KEYCODE_BUTTON_A (96)
B 1	0x09 0x0002	KEYCODE_BUTTON_B (97)
X1 _	0x09 0x0004	KEYCODE_BUTTON_X (99)
Y 1	0x09 0x0005	KEYCODE_BUTTON_Y (100)
D-pad up 1 D-pad down 1	0x01 0x0039 3	AXIS_HAT_Y 4
D-pad left 1 D-pad right 1	0x01 0x0039 3	AXIS_HAT_X 4
Left shoulder button 1	0x09 0x0007	KEYCODE_BUTTON_L1 (102)
Right shoulder button 1	0x09 0x0008	KEYCODE_BUTTON_R1 (103)
Left stick click 1	0x09 0x000E	KEYCODE_BUTTON_THUMBL (106)
Right stick click 1	0x09 0x000F	KEYCODE_BUTTON_THUMBR (107)
Casa 1	0x0c 0x0223	KEYCODE_HOME (3)
Atrás 1	0x0c 0x0224	KEYCODE_BACK (4)

1 [ Resources, 88 ]

2 The above HID usages must be declared within a Game pad CA (0x01 0x0005).

3 This usage must have a Logical Minimum of 0, a Logical Maximum of 7, a Physical Minimum of 0, a Physical Maximum of 315, Units in Degrees, and a Report Size of 4. The logical value is defined to be the clockwise rotation away from the vertical axis; for example, a logical value of 0 represents no rotation and the up button being pressed, while a logical value of 1 represents a rotation of 45 degrees and both the up and left keys being pressed.

4 [ Resources, 87 ]

Analog Controls 1	HID Usage	Botón Android
Gatillo izquierdo	0x02 0x00C5	AXIS_LTRIGGER
Gatillo derecho	0x02 0x00C4	AXIS_RTRIGGER
Palanca izquierda	0x01 0x0030 0x01 0x0031	AXIS_X AXIS_Y
Palanca derecha	0x01 0x0032 0x01 0x0035	AXIS_Z AXIS_RZ

1 [ Resources, 87 ]

7.2.7. Control remoto

Android Television device implementations SHOULD provide a remote control to allow users to access the TV interface. The remote control MAY be a physical remote or can be a software-based remote that is accessible from a mobile phone or tablet. The remote control MUST meet the requirements defined below.

• Search affordance . Device implementations MUST fire KEYCODE_SEARCH (or KEYCODE_ASSIST if the device supports an assistant) when the user invokes voice search on either the physical or software-based remote.
• Navegación . All Android Television remotes MUST include Back, Home, and Select buttons and support for D-pad events [ Resources, 88 ].

7.3. Sensores

Android includes APIs for accessing a variety of sensor types. Devices implementations generally MAY omit these sensors, as provided for in the following subsections. If a device includes a particular sensor type that has a corresponding API for third-party developers, the device implementation MUST implement that API as described in the Android SDK documentation and the Android Open Source documentation on sensors [ Resources, 89 ]. For example, device implementations:

• MUST accurately report the presence or absence of sensors per the android.content.pm.PackageManager class [ Resources, 70] .
• MUST return an accurate list of supported sensors via the SensorManager.getSensorList() and similar methods.
• MUST behave reasonably for all other sensor APIs (for example, by returning true or false as appropriate when applications attempt to register listeners, not calling sensor listeners when the corresponding sensors are not present; etc.).
• MUST report all sensor measurements using the relevant International System of Units (metric) values for each sensor type as defined in the Android SDK documentation [ Resources, 90 ].
• SHOULD report the event time in nanoseconds as defined in the Android SDK documentation, representing the time the event happened and synchronized with the SystemClock.elapsedRealtimeNano() clock. Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirement so they will be able to upgrade to the future platform releases where this might become a REQUIRED component. The synchronization error SHOULD be below 100 milliseconds [ Resources, 91 ].
• MUST report sensor data with a maximum latency of 100 milliseconds + 2 * sample_time for the case of a sensor streamed with a minimum required latency of 5 ms + 2 * sample_time when the application processor is active. This delay does not include any filtering delays.
• MUST report the first sensor sample within 400 milliseconds + 2 * sample_time of the sensor being activated. It is acceptable for this sample to have an accuracy of 0.

The list above is not comprehensive; the documented behavior of the Android SDK and the Android Open Source Documentations on Sensors [ Resources, 89 ] is to be considered authoritative.

Some sensor types are composite, meaning they can be derived from data provided by one or more other sensors. (Examples include the orientation sensor, and the linear acceleration sensor.) Device implementations SHOULD implement these sensor types, when they include the prerequisite physical sensors as described in [ Resources, 92 ]. If a device implementation includes a composite sensor it MUST implement the sensor as described in the Android Open Source documentation on composite sensors [ Resources, 92 ].

Some Android sensors support a “continuous” trigger mode, which returns data continuously [ Resources, 93 ]. For any API indicated by the Android SDK documentation to be a continuous sensor, device implementations MUST continuously provide periodic data samples that SHOULD have a jitter below 3%, where jitter is defined as the standard deviation of the difference of the reported timestamp values between consecutive eventos.

Note that the device implementations MUST ensure that the sensor event stream MUST NOT prevent the device CPU from entering a suspend state or waking up from a suspend state.

Finally, when several sensors are activated, the power consumption SHOULD NOT exceed the sum of the individual sensor's reported power consumption.

7.3.1. Acelerómetro

Device implementations SHOULD include a 3-axis accelerometer. Android Handheld devices and Android Watch devices are STRONGLY RECOMMENDED to include this sensor. If a device implementation does include a 3-axis accelerometer, it:

• MUST implement and report TYPE_ACCELEROMETER sensor [ Resources, 94 ].
• MUST be able to report events up to a frequency of at least 50 Hz for Android Watch devices as such devices have a stricter power constraint and 100 Hz for all other device types.
• SHOULD report events up to at least 200 Hz.
• MUST comply with the Android sensor coordinate system as detailed in the Android APIs [ Resources, 90 ].
• MUST be capable of measuring from freefall up to four times the gravity (4g) or more on any axis.
• MUST have a resolution of at least 12-bits and SHOULD have a resolution of at least 16-bits.
• SHOULD be calibrated while in use if the characteristics changes over the life cycle and compensated, and preserve the compensation parameters between device reboots.
• SHOULD be temperature compensated.
• MUST have a standard deviation no greater than 0.05 m/s^, where the standard deviation should be calculated on a per axis basis on samples collected over a period of at least 3 seconds at the fastest sampling rate.
• SHOULD implement the TYPE_SIGNIFICANT_MOTION, TYPE_TILT_DETECTOR, TYPE_STEP_DETECTOR, TYPE_STEP_COUNTER composite sensors as described in the Android SDK document. Existing and new Android devices are STRONGLY RECOMMENDED to implement the TYPE_SIGNIFICANT_MOTION composite sensor. If any of these sensors are implemented, the sum of their power consumption MUST always be less than 4 mW and SHOULD each be below 2 mW and 0.5 mW for when the device is in a dynamic or static condition.
• If a gyroscope sensor is included, MUST implement the TYPE_GRAVITY and TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices are STRONGLY RECOMMENDED to implement the TYPE_GAME_ROTATION_VECTOR sensor.
• MUST implement a TYPE_ROTATION_VECTOR composite sensor, if a gyroscope sensor and a magnetometer sensor is also included.

7.3.2. Magnetómetro

Device implementations SHOULD include a 3-axis magnetometer (compass). If a device does include a 3-axis magnetometer, it:

• MUST implement the TYPE_MAGNETIC_FIELD sensor and SHOULD also implement TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor. Existing and new Android devices are STRONGLY RECOMMENDED to implement the TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor.
• MUST be able to report events up to a frequency of at least 10 Hz and SHOULD report events up to at least 50 Hz.
• MUST comply with the Android sensor coordinate system as detailed in the Android APIs [ Resources, 90 ].
• MUST be capable of measuring between -900 µT and +900 µT on each axis before saturating.
• MUST have a hard iron offset value less than 700 µT and SHOULD have a value below 200 µT, by placing the magnetometer far from dynamic (current-induced) and static (magnet-induced) magnetic fields.
• MUST have a resolution equal or denser than 0.6 µT and SHOULD have a resolution equal or denser than 0.2 µ.
• SHOULD be temperature compensated.
• MUST support online calibration and compensation of the hard iron bias, and preserve the compensation parameters between device reboots.
• MUST have the soft iron compensation applied—the calibration can be done either while in use or during the production of the device.
• SHOULD have a standard deviation, calculated on a per axis basis on samples collected over a period of at least 3 seconds at the fastest sampling rate, no greater than 0.5 µT.
• MUST implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer sensor and a gyroscope sensor is also included.
• MAY implement the TYPE_GEOMAGNETIC_ROTATION_VECTOR sensor if an accelerometer sensor is also implemented. However if implemented, it MUST consume less than 10 mW and SHOULD consume less than 3 mW when the sensor is registered for batch mode at 10 Hz.

7.3.3. GPS

Device implementations SHOULD include a GPS receiver. If a device implementation does include a GPS receiver, it SHOULD include some form of“assisted GPS” technique to minimize GPS lock-on time.

7.3.4. Giroscopio

Device implementations SHOULD include a gyroscope (angular change sensor). Devices SHOULD NOT include a gyroscope sensor unless a 3-axis accelerometer is also included. If a device implementation includes a gyroscope, it:

• MUST implement the TYPE_GYROSCOPE sensor and SHOULD also implement TYPE_GYROSCOPE_UNCALIBRATED sensor. Existing and new Android devices are STRONGLY RECOMMENDED to implement the SENSOR_TYPE_GYROSCOPE_UNCALIBRATED sensor.
• MUST be capable of measuring orientation changes up to 1,000 degrees per second.
• MUST be able to report events up to a frequency of at least 50 Hz for Android Watch devices as such devices have a stricter power constraint and 100 Hz for all other device types.
• SHOULD report events up to at least 200 Hz.
• MUST have a resolution of 12-bits or more and SHOULD have a resolution of 16-bits or more.
• MUST be temperature compensated.
• MUST be calibrated and compensated while in use, and preserve the compensation parameters between device reboots.
• MUST have a variance no greater than 1e-7 rad^2 / s^2 per Hz (variance per Hz, or rad^2 / s). The variance is allowed to vary with the sampling rate, but must be constrained by this value. In other words, if you measure the variance of the gyro at 1 Hz sampling rate it should be no greater than 1e-7 rad^2/s^2.
• MUST implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer sensor and a magnetometer sensor is also included.
• If an accelerometer sensor is included, MUST implement the TYPE_GRAVITY and TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices are STRONGLY RECOMMENDED to implement the TYPE_GAME_ROTATION_VECTOR sensor.

7.3.5. Barómetro

Device implementations SHOULD include a barometer (ambient air pressure sensor). If a device implementation includes a barometer, it:

• MUST implement and report TYPE_PRESSURE sensor.
• MUST be able to deliver events at 5 Hz or greater.
• MUST have adequate precision to enable estimating altitude.
• MUST be temperature compensated.

7.3.6. Termómetro

Device implementations MAY include an ambient thermometer (temperature sensor). If present, it MUST be defined as SENSOR_TYPE_AMBIENT_TEMPERATURE and it MUST measure the ambient (room) temperature in degrees Celsius.

Device implementations MAY but SHOULD NOT include a CPU temperature sensor. If present, it MUST be defined as SENSOR_TYPE_TEMPERATURE, it MUST measure the temperature of the device CPU, and it MUST NOT measure any other temperature. Note the SENSOR_TYPE_TEMPERATURE sensor type was deprecated in Android 4.0.

7.3.7. Fotómetro

Device implementations MAY include a photometer (ambient light sensor).

7.3.8. Sensor de proximidad

Device implementations MAY include a proximity sensor. Devices that can make a voice call and indicate any value other than PHONE_TYPE_NONE in getPhoneType SHOULD include a proximity sensor. If a device implementation does include a proximity sensor, it:

• MUST measure the proximity of an object in the same direction as the screen. That is, the proximity sensor MUST be oriented to detect objects close to the screen, as the primary intent of this sensor type is to detect a phone in use by the user. If a device implementation includes a proximity sensor with any other orientation, it MUST NOT be accessible through this API.
• MUST have 1-bit of accuracy or more.

7.3.9. High Fidelity Sensors

Device implementations supporting a set of higher quality sensors that can meet all the requirements listed in this section MUST identify the support through the android.hardware.sensor.hifi_sensors feature flag.

A device declaring android.hardware.sensor.hifi_sensors MUST support all of the following sensor types meeting the quality requirements as below:

• SENSOR_TYPE_ACCELEROMETER
  • MUST have a measurement range between at least -8g and +8g
  • MUST have a measurement resolution of at least 1024 LSB/G
  • MUST have a minimum measurement frequency of 12.5 Hz or lower
  • MUST have a maxmium measurement frequency of 200 Hz or higher
  • MUST have a measurement noise not above 400uG/√Hz
  • MUST implement a non-wake-up form of this sensor with a buffering capability of at least 3000 sensor events
  • MUST have a batching power consumption not worse than 3 mW
• SENSOR_TYPE_GYROSCOPE
  • MUST have a measurement range between at least -1000 and +1000 dps
  • MUST have a measurement resolution of at least 16 LSB/dps
  • MUST have a minimum measurement frequency of 12.5 Hz or lower
  • MUST have a maxmium measurement frequency of 200 Hz or higher
  • MUST have a measurement noise not above 0.014°/s/√Hz
• SENSOR_TYPE_GYROSCOPE_UNCALIBRATED with the same quality requirements as SENSOR_TYPE_GYROSCOPE
• SENSOR_TYPE_GEOMAGNETIC_FIELD
  • MUST have a measurement range between at least -900 and +900 uT
  • MUST have a measurement resolution of at least 5 LSB/uT
  • MUST have a minimum measurement frequency of 5 Hz or lower
  • MUST have a maxmium measurement frequency of 50 Hz or higher
  • MUST have a measurement noise not above 0.5 uT
• SENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED with the same quality requirements as SENSOR_TYPE_GEOMAGNETIC_FIELD and in addition:
  • MUST implement a non-wake-up form of this sensor with a buffering capability of at least 600 sensor events
• SENSOR_TYPE_PRESSURE
  • MUST have a measurement range between at least 300 and 1100 hPa
  • MUST have a measurement resolution of at least 80 LSB/hPa
  • MUST have a minimum measurement frequency of 1 Hz or lower
  • MUST have a maximum measurement frequency of 10 Hz or higher
  • MUST have a measurement noise not above 2 Pa/√Hz
  • MUST implement a non-wake-up form of this sensor with a buffering capability of at least 300 sensor events
  • MUST have a batching power consumption not worse than 2 mW
• TYPE_GAME_ROTATION_VECTOR
  • MUST implement a non-wake-up form of this sensor with a buffering capability of at least 300 sensor events.
  • MUST have a batching power consumption not worse than 4 mW.
• SENSOR_TYPE_SIGNIFICANT_MOTION
  • MUST have a power consumption not worse than 0.5 mW when device is static and 1.5 mW when device is moving
• SENSOR_TYPE_STEP_DETECTOR
  • MUST implement a non-wake-up form of this sensor with a buffering capability of at least 100 sensor events
  • MUST have a power consumption not worse than 0.5 mW when device is static and 1.5 mW when device is moving
  • MUST have a batching power consumption not worse than 4 mW
• SENSOR_TYPE_STEP_COUNTER
  • MUST have a power consumption not worse than 0.5 mW when device is static and 1.5 mW when device is moving
• SENSOR_TILT_DETECTOR
  • MUST have a power consumption not worse than 0.5 mW when device is static and 1.5 mW when device is moving

Also such a device MUST meet the following sensor subsystem requirements:

• The event timestamp of the same physical event reported by the Accelerometer, Gyroscope sensor and Magnetometer MUST be within 2.5 milliseconds of each other.
• The Gyroscope sensor event timestamps MUST be on the same time base as the camera subsystem and within 1 millisconds of error.
• The latency of delivery of samples to the HAL SHOULD be below 5 milliseconds from the instant the data is available on the physical sensor hardware.
• The power consumption MUST not be higher than 0.5 mW when device is static and 2.0 mW when device is moving when any combination of the following sensors are enabled:
  • SENSOR_TYPE_SIGNIFICANT_MOTION
  • SENSOR_TYPE_STEP_DETECTOR
  • SENSOR_TYPE_STEP_COUNTER
  • SENSOR_TILT_DETECTORS

Note that all power consumption requirements in this section do not include the power consumption of the Application Processor. It is inclusive of the power drawn by the entire sensor chain - the sensor, any supporting circuitry, any dedicated sensor processing system, etc.

The following sensor types MAY also be supported on a device implementation declaring android.hardware.sensor.hifi_sensors, but if these sensor types are present they MUST meet the following minimum buffering capability requirement:

• SENSOR_TYPE_PROXIMITY: 100 sensor events

7.3.10. Sensor de huellas dactilares

Device implementations with a secure lock screen SHOULD include a fingerprint sensor. If a device implementation includes a fingerprint sensor and has a corresponding API for third-party developers, it:

• MUST declare support for the android.hardware.fingerprint feature.
• MUST fully implement the corresponding API as described in the Android SDK documentation [ Resources, 95 ].
• MUST have a false acceptance rate not higher than 0.002%.
• Is STRONGLY RECOMMENDED to have a false rejection rate of less than 10%, as measured on the device
• Is STRONGLY RECOMMENDED to have a latency below 1 second, measured from when the fingerprint sensor is touched until the screen is unlocked, for one enrolled finger.
• MUST rate limit attempts for at least 30 seconds after five false trials for fingerprint verification.
• MUST have a hardware-backed keystore implementation, and perform the fingerprint matching in a Trusted Execution Environment (TEE) or on a chip with a secure channel to the TEE.
• MUST have all identifiable fingerprint data encrypted and cryptographically authenticated such that they cannot be acquired, read or altered outside of the Trusted Execution Environment (TEE) as documented in the implementation guidelines on the Android Open Source Project site [ Resources, 96 ].
• MUST prevent adding a fingerprint without first establishing a chain of trust by having the user confirm existing or add a new device credential (PIN/pattern/password) that's secured by TEE; the Android Open Source Project implementation provides the mechanism in the framework to do so.
• MUST NOT enable 3rd-party applications to distinguish between individual fingerprints.
• MUST honor the DevicePolicyManager.KEYGUARD_DISABLE_FINGERPRINT flag.
• MUST, when upgraded from a version earlier than Android 6.0, have the fingerprint data securely migrated to meet the above requirements or removed.
• SHOULD use the Android Fingerprint icon provided in the Android Open Source Project.

7.4. Conectividad de datos

7.4.1. Telefonía

“Telephony” as used by the Android APIs and this document refers specifically to hardware related to placing voice calls and sending SMS messages via a GSM or CDMA network. While these voice calls may or may not be packet-switched, they are for the purposes of Android considered independent of any data connectivity that may be implemented using the same network. In other words, the Android “telephony” functionality and APIs refer specifically to voice calls and SMS. For instance, device implementations that cannot place calls or send/receive SMS messages MUST NOT report the android.hardware.telephony feature or any subfeatures, regardless of whether they use a cellular network for data connectivity.

Android MAY be used on devices that do not include telephony hardware. That is, Android is compatible with devices that are not phones. However, if a device implementation does include GSM or CDMA telephony, it MUST implement full support for the API for that technology. Device implementations that do not include telephony hardware MUST implement the full APIs as no-ops.

7.4.2. IEEE 802.11 (Wi-Fi)

Android Television device implementations MUST include support for one or more forms of 802.11 (b/g/a/n, etc.) and other types of Android device implementation SHOULD include support for one or more forms of 802.11. If a device implementation does include support for 802.11 and exposes the functionality to a third-party application, it MUST implement the corresponding Android API and:

• MUST report the hardware feature flag android.hardware.wifi.
• MUST implement the multicast API as described in the SDK documentation [ Resources, 97 ].
• MUST support multicast DNS (mDNS) and MUST NOT filter mDNS packets (224.0.0.251) at any time of operation including:
  • Even when the screen is not in an active state.
  • For Android Television device implementations, even when in standby power states.

7.4.2.1. Wi-Fi directo

Device implementations SHOULD include support for Wi-Fi Direct (Wi-Fi peer-to-peer). If a device implementation does include support for Wi-Fi Direct, it MUST implement the corresponding Android API as described in the SDK documentation [ Resources, 98 ]. If a device implementation includes support for Wi-Fi Direct, then it:

• MUST report the hardware feature android.hardware.wifi.direct.
• MUST support regular Wi-Fi operation.
• SHOULD support concurrent Wi-Fi and Wi-Fi Direct operation.

7.4.2.2. Wi-Fi Tunneled Direct Link Setup

Android Television device implementations MUST include support for Wi-Fi Tunneled Direct Link Setup (TDLS) and other types of Android device implementations SHOULD include support for Wi-Fi TDLS as described in the Android SDK Documentation [ Resources, 99 ]. If a device implementation does include support for TDLS and TDLS is enabled by the WiFiManager API, the device:

• SHOULD use TDLS only when it is possible AND beneficial.
• SHOULD have some heuristic and NOT use TDLS when its performance might be worse than going through the Wi-Fi access point.

7.4.3. Bluetooth

Android includes support for Bluetooth and Bluetooth Low Energy [ Resources, 100 ]. Device implementations that include support for Bluetooth and Bluetooth Low Energy MUST declare the relevant platform features (android.hardware.bluetooth and android.hardware.bluetooth_le respectively) and implement the platform APIs. Device implementations SHOULD implement relevant Bluetooth profiles such as A2DP, AVCP, OBEX, etc. as appropriate for the device. Android Television device implementations MUST support Bluetooth and Bluetooth LE.

Device implementations including support for Bluetooth Low Energy:

• MUST declare the hardware feature android.hardware.bluetooth_le.
• MUST enable the GATT (generic attribute profile) based Bluetooth APIs as described in the SDK documentation and [ Resources, 100 ].
• are STRONGLY RECOMMENDED to implement a Resolvable Private Address (RPA) timeout no longer than 15 minutes and rotate the address at timeout to protect user privacy.
• SHOULD support offloading of the filtering logic to the bluetooth chipset when implementing the ScanFilter API [ Resources, 101 ], and MUST report the correct value of where the filtering logic is implemented whenever queried via the android.bluetooth.BluetoothAdapter.isOffloadedFilteringSupported() method.
• SHOULD support offloading of the batched scanning to the bluetooth chipset, but if not supported, MUST report 'false' whenever queried via the android.bluetooth.BluetoothAdapater.isOffloadedScanBatchingSupported() method.
• SHOULD support multi advertisement with at least 4 slots, but if not supported, MUST report 'false' whenever queried via the android.bluetooth.BluetoothAdapter.isMultipleAdvertisementSupported() method.

7.4.4. Comunicaciones de campo cercano

Device implementations SHOULD include a transceiver and related hardware for Near-Field Communications (NFC). If a device implementation does include NFC hardware and plans to make it available to third-party apps, then it:

• MUST report the android.hardware.nfc feature from the android.content.pm.PackageManager.hasSystemFeature() method [ Resources, 70 ].
• MUST be capable of reading and writing NDEF messages via the following NFC standards:
  • MUST be capable of acting as an NFC Forum reader/writer (as defined by the NFC Forum technical specification NFCForum-TS-DigitalProtocol-1.0) via the following NFC standards:
    • NfcA (ISO14443-3A)
    • NfcB (ISO14443-3B)
    • NfcF (JIS X 6319-4)
    • IsoDep (ISO 14443-4)
    • NFC Forum Tag Types 1, 2, 3, 4 (defined by the NFC Forum)
  • STRONGLY RECOMMENDED to be capable of reading and writing NDEF messages as well as raw data via the following NFC standards. Note that while the NFC standards below are stated as STRONGLY RECOMMENDED, the Compatibility Definition for a future version is planned to change these to MUST. These standards are optional in this version but will be required in future versions. Existing and new devices that run this version of Android are very strongly encouraged to meet these requirements now so they will be able to upgrade to the future platform releases.
    • NfcV (ISO 15693)
  • SHOULD be capable of reading the barcode and URL (if encoded) of Thinfilm NFC Barcode [ Resources, 102 ] products.
  • MUST be capable of transmitting and receiving data via the following peer-to-peer standards and protocols:
    • ISO 18092
    • LLCP 1.2 (defined by the NFC Forum)
    • SDP 1.0 (defined by the NFC Forum)
    • NDEF Push Protocol [ Resources, 103 ]
    • SNEP 1.0 (defined by the NFC Forum)
  • MUST include support for Android Beam [ Resources, 104 ]:
    • MUST implement the SNEP default server. Valid NDEF messages received by the default SNEP server MUST be dispatched to applications using the android.nfc.ACTION_NDEF_DISCOVERED intent. Disabling Android Beam in settings MUST NOT disable dispatch of incoming NDEF message.
    • MUST honor the android.settings.NFCSHARING_SETTINGS intent to show NFC sharing settings [ Resources, 105 ].
    • MUST implement the NPP server. Messages received by the NPP server MUST be processed the same way as the SNEP default server.
    • MUST implement a SNEP client and attempt to send outbound P2P NDEF to the default SNEP server when Android Beam is enabled. If no default SNEP server is found then the client MUST attempt to send to an NPP server.
    • MUST allow foreground activities to set the outbound P2P NDEF message using android.nfc.NfcAdapter.setNdefPushMessage, and android.nfc.NfcAdapter.setNdefPushMessageCallback, and android.nfc.NfcAdapter.enableForegroundNdefPush.
    • SHOULD use a gesture or on-screen confirmation, such as 'Touch to Beam', before sending outbound P2P NDEF messages.
    • SHOULD enable Android Beam by default and MUST be able to send and receive using Android Beam, even when another proprietary NFC P2p mode is turned on.
    • MUST support NFC Connection handover to Bluetooth when the device supports Bluetooth Object Push Profile. Device implementations MUST support connection handover to Bluetooth when using android.nfc.NfcAdapter.setBeamPushUris, by implementing the “Connection Handover version 1.2” [ Resources, 106 ] and “Bluetooth Secure Simple Pairing Using NFC version 1.0” [ Resources, 107 ] specs from the NFC Forum. Such an implementation MUST implement the handover LLCP service with service name “urn:nfc:sn:handover” for exchanging the handover request/select records over NFC, and it MUST use the Bluetooth Object Push Profile for the actual Bluetooth data transfer. For legacy reasons (to remain compatible with Android 4.1 devices), the implementation SHOULD still accept SNEP GET requests for exchanging the handover request/select records over NFC. However an implementation itself SHOULD NOT send SNEP GET requests for performing connection handover.
  • MUST poll for all supported technologies while in NFC discovery mode.
  • SHOULD be in NFC discovery mode while the device is awake with the screen active and the lock-screen unlocked.

(Note that publicly available links are not available for the JIS, ISO, and NFC Forum specifications cited above.)

Android includes support for NFC Host Card Emulation (HCE) mode. If a device implementation does include an NFC controller chipset capable of HCE and Application ID (AID) routing, then it:

• MUST report the android.hardware.nfc.hce feature constant.
• MUST support NFC HCE APIs as defined in the Android SDK [ Resources, 108 ].

Additionally, device implementations MAY include reader/writer support for the following MIFARE technologies.

• MIFARE Clásico
• MIFARE Ultraligero
• NDEF on MIFARE Classic

Note that Android includes APIs for these MIFARE types. If a device implementation supports MIFARE in the reader/writer role, it:

• MUST implement the corresponding Android APIs as documented by the Android SDK.
• MUST report the feature com.nxp.mifare from the android.content.pm.PackageManager.hasSystemFeature() method [ Resources, 70 ]. Note that this is not a standard Android feature and as such does not appear as a constant in the android.content.pm.PackageManager class.
• MUST NOT implement the corresponding Android APIs nor report the com.nxp.mifare feature unless it also implements general NFC support as described in this section.

If a device implementation does not include NFC hardware, it MUST NOT declare the android.hardware.nfc feature from the android.content.pm.PackageManager.hasSystemFeature() method [ Resources, 70 ], and MUST implement the Android NFC API as a no-op.

As the classes android.nfc.NdefMessage and android.nfc.NdefRecord represent a protocol-independent data representation format, device implementations MUST implement these APIs even if they do not include support for NFC or declare the android.hardware.nfc feature.

7.4.5. Minimum Network Capability

Device implementations MUST include support for one or more forms of data networking. Specifically, device implementations MUST include support for at least one data standard capable of 200Kbit/sec or greater. Examples of technologies that satisfy this requirement include EDGE, HSPA, EV-DO, 802.11g, Ethernet, Bluetooth PAN, etc.

Device implementations where a physical networking standard (such as Ethernet) is the primary data connection SHOULD also include support for at least one common wireless data standard, such as 802.11 (Wi-Fi).

Devices MAY implement more than one form of data connectivity.

Devices MUST include an IPv6 networking stack and support IPv6 communication using the managed APIs, such as java.net.Socket and java.net.URLConnection , as well as the native APIs, such as AF_INET6 sockets. The required level of IPv6 support depends on the network type, as follows:

• Devices that support Wi-Fi networks MUST support dual-stack and IPv6-only operation on Wi-Fi.
• Devices that support Ethernet networks MUST support dual-stack operation on Ethernet.
• Devices that support cellular data SHOULD support IPv6 operation (IPv6-only and possibly dual-stack) on cellular data.
• When a device is simultaneously connected to more than one network (eg, Wi-Fi and cellular data), it MUST simultaneously meet these requirements on each network to which it is connected.

IPv6 MUST be enabled by default.

In order to ensure that IPv6 communication is as reliable as IPv4, unicast IPv6 packets sent to the device MUST NOT be dropped, even when the screen is not in an active state. Redundant multicast IPv6 packets, such as repeated identical Router Advertisements, MAY be rate-limited in hardware or firmware if doing so is necessary to save power. In such cases, rate-limiting MUST NOT cause the device to lose IPv6 connectivity on any IPv6-compliant network that uses RA lifetimes of at least 180 seconds.

IPv6 connectivity MUST be maintained in doze mode.

7.4.6. Configuración de sincronización

Device implementations MUST have the master auto-sync setting on by default so that the method getMasterSyncAutomatically() returns “true” [ Resources, 109 ].

7.5. Cámaras

Device implementations SHOULD include a rear-facing camera and MAY include a front-facing camera. A rear-facing camera is a camera located on the side of the device opposite the display; that is, it images scenes on the far side of the device, like a traditional camera. A front-facing camera is a camera located on the same side of the device as the display; that is, a camera typically used to image the user, such as for video conferencing and similar applications.

If a device implementation includes at least one camera, it SHOULD be possible for an application to simultaneously allocate 3 bitmaps equal to the size of the images produced by the largest-resolution camera sensor on the device.

7.5.1. Rear-Facing Camera

Device implementations SHOULD include a rear-facing camera. If a device implementation includes at least one rear-facing camera, it:

• MUST report the feature flag android.hardware.camera and android.hardware.camera.any.
• MUST have a resolution of at least 2 megapixels.
• SHOULD have either hardware auto-focus or software auto-focus implemented in the camera driver (transparent to application software).
• MAY have fixed-focus or EDOF (extended depth of field) hardware.
• MAY include a flash. If the Camera includes a flash, the flash lamp MUST NOT be lit while an android.hardware.Camera.PreviewCallback instance has been registered on a Camera preview surface, unless the application has explicitly enabled the flash by enabling the FLASH_MODE_AUTO or FLASH_MODE_ON attributes of a Camera.Parameters object. Note that this constraint does not apply to the device's built-in system camera application, but only to third-party applications using Camera.PreviewCallback.

7.5.2. Cámara frontal

Device implementations MAY include a front-facing camera. If a device implementation includes at least one front-facing camera, it:

• MUST report the feature flag android.hardware.camera.any and android.hardware.camera.front.
• MUST have a resolution of at least VGA (640x480 pixels).
• MUST NOT use a front-facing camera as the default for the Camera API. The camera API in Android has specific support for front-facing cameras and device implementations MUST NOT configure the API to to treat a front-facing camera as the default rear-facing camera, even if it is the only camera on the device.
• MAY include features (such as auto-focus, flash, etc.) available to rear-facing cameras as described in section 7.5.1 .
• MUST horizontally reflect (ie mirror) the stream displayed by an app in a CameraPreview, as follows:
  • If the device implementation is capable of being rotated by user (such as automatically via an accelerometer or manually via user input), the camera preview MUST be mirrored horizontally relative to the device's current orientation.
  • If the current application has explicitly requested that the Camera display be rotated via a call to the android.hardware.Camera.setDisplayOrientation()[ Resources, 110 ] method, the camera preview MUST be mirrored horizontally relative to the orientation specified by the application.
  • Otherwise, the preview MUST be mirrored along the device's default horizontal axis.
• MUST mirror the image displayed by the postview in the same manner as the camera preview image stream. If the device implementation does not support postview, this requirement obviously does not apply.
• MUST NOT mirror the final captured still image or video streams returned to application callbacks or committed to media storage.

7.5.3. Cámara externa

Device implementations with USB host mode MAY include support for an external camera that connects to the USB port. If a device includes support for an external camera, it:

• MUST declare the platform feature android.hardware.camera.external and android.hardware camera.any.
• MUST support USB Video Class (UVC 1.0 or higher).
• MAY support multiple cameras.

Video compression (such as MJPEG) support is RECOMMENDED to enable transfer of high-quality unencoded streams (ie raw or independently compressed picture streams). Camera-based video encoding MAY be supported. If so, a simultaneous unencoded/ MJPEG stream (QVGA or greater resolution) MUST be accessible to the device implementation.

7.5.4. Camera API Behavior

Android includes two API packages to access the camera, the newer android.hardware.camera2 API expose lower-level camera control to the app, including efficient zero-copy burst/streaming flows and per-frame controls of exposure, gain, white balance gains, color conversion, denoising, sharpening, and more.

The older API package, android.hardware.Camera, is marked as deprecated in Android 5.0 but as it should still be available for apps to use Android device implementations MUST ensure the continued support of the API as described in this section and in the Android SDK .

Device implementations MUST implement the following behaviors for the camera-related APIs, for all available cameras:

• If an application has never called android.hardware.Camera.Parameters.setPreviewFormat(int), then the device MUST use android.hardware.PixelFormat.YCbCr_420_SP for preview data provided to application callbacks.
• If an application registers an android.hardware.Camera.PreviewCallback instance and the system calls the onPreviewFrame() method when the preview format is YCbCr_420_SP, the data in the byte[] passed into onPreviewFrame() must further be in the NV21 encoding format. That is, NV21 MUST be the default.
• For android.hardware.Camera, device implementations MUST support the YV12 format (as denoted by the android.graphics.ImageFormat.YV12 constant) for camera previews for both front- and rear-facing cameras. (The hardware video encoder and camera may use any native pixel format, but the device implementation MUST support conversion to YV12.)
• For android.hardware.camera2, device implementations must support the android.hardware.ImageFormat.YUV_420_888 and android.hardware.ImageFormat.JPEG formats as outputs through the android.media.ImageReader API.

Device implementations MUST still implement the full Camera API included in the Android SDK documentation [ Resources, 111 ], regardless of whether the device includes hardware autofocus or other capabilities. For instance, cameras that lack autofocus MUST still call any registered android.hardware.Camera.AutoFocusCallback instances (even though this has no relevance to a non-autofocus camera.) Note that this does apply to front-facing cameras; for instance, even though most front-facing cameras do not support autofocus, the API callbacks must still be “faked” as described.

Device implementations MUST recognize and honor each parameter name defined as a constant on the android.hardware.Camera.Parameters class, if the underlying hardware supports the feature. If the device hardware does not support a feature, the API must behave as documented. Conversely, device implementations MUST NOT honor or recognize string constants passed to the android.hardware.Camera.setParameters() method other than those documented as constants on the android.hardware.Camera.Parameters. That is, device implementations MUST support all standard Camera parameters if the hardware allows, and MUST NOT support custom Camera parameter types. For instance, device implementations that support image capture using high dynamic range (HDR) imaging techniques MUST support camera parameter Camera.SCENE_MODE_HDR [ Resources, 112 ].

Because not all device implementations can fully support all the features of the android.hardware.camera2 API, device implementations MUST report the proper level of support with the android.info.supportedHardwareLevel property as described in the Android SDK [ Resources, 113 ] and report the appropriate framework feature flags [ Resources, 114 ].

Device implementations MUST also declare its Individual camera capabilities of android.hardware.camera2 via the android.request.availableCapabilities property and declare the appropriate feature flags [ Resources, 114 ]; a device must define the feature flag if any of its attached camera devices supports the feature.

Device implementations MUST broadcast the Camera.ACTION_NEW_PICTURE intent whenever a new picture is taken by the camera and the entry of the picture has been added to the media store.

Device implementations MUST broadcast the Camera.ACTION_NEW_VIDEO intent whenever a new video is recorded by the camera and the entry of the picture has been added to the media store.

7.5.5. Orientación de la cámara

Both front- and rear-facing cameras, if present, MUST be oriented so that the long dimension of the camera aligns with the screen's long dimension. That is, when the device is held in the landscape orientation, cameras MUST capture images in the landscape orientation. This applies regardless of the device's natural orientation; that is, it applies to landscape-primary devices as well as portrait-primary devices.

7.6. Memoria y almacenamiento

7.6.1. Memoria y almacenamiento mínimos

The memory available to the kernel and userspace on device implementations MUST be at least equal or larger than the minimum values specified by the following table. (See section 7.1.1 for screen size and density definitions.)

Density and screen size	32-bit device	64-bit device
Android Watch devices (due to smaller screens)	416MB	No aplica
280dpi or lower on small/normal screens mdpi or lower on large screens ldpi or lower on extra large screens	424MB	704MB
xhdpi or higher on small/normal screens hdpi or higher on large screens mdpi or higher on extra large screens	512MB	832MB
400dpi or higher on small/normal screens xhdpi or higher on large screens tvdpi or higher on extra large screens	896MB	1280MB
560dpi or higher on small/normal screens 400dpi or higher on large screens xhdpi or higher on extra large screens	1344MB	1824MB

The minimum memory values MUST be in addition to any memory space already dedicated to hardware components such as radio, video, and so on that is not under the kernel's control.

Device implementations with less than 512MB of memory available to the kernel and userspace, unless an Android Watch, MUST return the value "true" for ActivityManager.isLowRamDevice().

Android Television devices MUST have at least 5GB and other device implementations MUST have at least 1.5GB of non-volatile storage available for application private data. That is, the /data partition MUST be at least 5GB for Android Television devices and at least 1.5GB for other device implementations. Device implementations that run Android are STRONGLY RECOMMENDED to have at least 3GB of non-volatile storage for application private data so they will be able to upgrade to the future platform releases.

The Android APIs include a Download Manager that applications MAY use to download data files [ Resources, 115 ]. The device implementation of the Download Manager MUST be capable of downloading individual files of at least 100MB in size to the default “cache" location.

7.6.2. Application Shared Storage

Device implementations MUST offer shared storage for applications also often referred as “shared external storage”.

Device implementations MUST be configured with shared storage mounted by default, “out of the box”. If the shared storage is not mounted on the Linux path /sdcard, then the device MUST include a Linux symbolic link from /sdcard to the actual mount point.

Device implementations MAY have hardware for user-accessible removable storage, such as a Secure Digital (SD) card slot. If this slot is used to satisfy the shared storage requirement, the device implementation:

• MUST implement a toast or pop-up user interface warning the user when there is no SD card.
• MUST include a FAT-formatted SD card 1GB in size or larger OR show on the box and other material available at time of purchase that the SD card has to be separately purchased.
• MUST mount the SD card by default.

Alternatively, device implementations MAY allocate internal (non-removable) storage as shared storage for apps as included in the upstream Android Open Source Project; device implementations SHOULD use this configuration and software implementation. If a device implementation uses internal (non-removable) storage to satisfy the shared storage requirement, while that storage MAY share space with the application private data, it MUST be at least 1GB in size and mounted on /sdcard (or /sdcard MUST be a symbolic link to the physical location if it is mounted elsewhere).

Device implementations MUST enforce as documented the android.permission.WRITE_EXTERNAL_STORAGE permission on this shared storage. Shared storage MUST otherwise be writable by any application that obtains that permission.

Device implementations that include multiple shared storage paths (such as both an SD card slot and shared internal storage) MUST allow only pre-installed & privileged Android applications with the WRITE_EXTERNAL_STORAGE permission to write to the secondary external storage, except when writing to their package-specific directories or within the URI returned by firing the ACTION_OPEN_DOCUMENT_TREE intent.

However, device implementations SHOULD expose content from both storage paths transparently through Android's media scanner service and android.provider.MediaStore.

Regardless of the form of shared storage used, if the device implementation has a USB port with USB peripheral mode support, it MUST provide some mechanism to access the contents of shared storage from a host computer. Device implementations MAY use USB mass storage, but SHOULD use Media Transfer Protocol to satisfy this requirement. If the device implementation supports Media Transfer Protocol, it:

• SHOULD be compatible with the reference Android MTP host, Android File Transfer [ Resources, 116 ].
• SHOULD report a USB device class of 0x00.
• SHOULD report a USB interface name of 'MTP'.

7.6.3. Almacenamiento adoptable

Device implementations are STRONGLY RECOMMENDED to implement adoptable storage if the removable storage device port is in a long-term stable location, such as within the battery compartment or other protective cover [ Resources, 117 ].

Device implementations such as a television, MAY enable adoption through USB ports as the device is expected to be static and not mobile. But for other device implementations that are mobile in nature, it is STRONGLY RECOMMENDED to implement the adoptable storage in a long-term stable location, since accidentally disconnecting them can cause data loss/corruption.

7.7. USB

Device implementations SHOULD support USB peripheral mode and SHOULD support USB host mode.

If a device implementation includes a USB port supporting peripheral mode:

• The port MUST be connectable to a USB host that has a standard type-A or type -C USB port.
• The port SHOULD use micro-B, micro-AB or Type-C USB form factor. Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements so they will be able to upgrade to future platform releases.
• The port SHOULD either be located on the bottom of the device (according to natural orientation) or enable software screen rotation for all apps (including home screen), so that the display draws correctly when the device is oriented with the port at bottom. Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements so they will be able to upgrade to future platform releases.
• It SHOULD implement the Android Open Accessory (AOA) API and specification as documented in the Android SDK documentation, and if it is an Android Handheld device it MUST implement the AOA API. Device implementations implementing the AOA specification:
  • MUST declare support for the hardware feature android.hardware.usb.accessory [ Resources, 118 ].
  • MUST support establishing an AOA protocol based communication on first time connection with a USB host machine that acts as an accessory, without the need for the user to change the default USB mode.
  • MUST implement the USB audio class as documented in the Android SDK documentation [ Resources, 119 ].
  • And also the USB mass storage class, MUST include the string "android" at the end of the interface description iInterface string of the USB mass storage
• It SHOULD implement support to draw 1.5 A current during HS chirp and traffic as specified in the USB Battery Charging Specification, Revision 1.2 [ Resources, 120 ]. Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements so they will be able to upgrade to the future platform releases.
the Type-C resistor standard.
• The value of iSerialNumber in USB standard device descriptor MUST be equal to the value of android.os.Build.SERIAL.

If a device implementation includes a USB port supporting host mode, it:

• SHOULD use a type-C USB port, if the device implementation supports USB 3.1.
• MAY use a non-standard port form factor, but if so MUST ship with a cable or cables adapting the port to a standard type-A or type-C USB port.
• MAY use a micro-AB USB port, but if so SHOULD ship with a cable or cables adapting the port to a standard type-A or type-C USB port.
• is STRONGLY RECOMMENDED to implement the USB audio class as documented in the Android SDK documentation [ Resources, 119 ].
• MUST implement the Android USB host API as documented in the Android SDK, and MUST declare support for the hardware feature android.hardware.usb.host [ Resources, 121 ].
• SHOULD support device charging while in host mode; advertising a source current of at least 1.5A as specified in the Termination Parameters section of the USB Type-C Cable and Connector Specification, Revision 1.2 [ ] for USB Type-C connectors or using Charging Downstream Port(CDP) output current range as specified in the USB Battery Charging Specification, Revision 1.2 [ Resources, 120 ] for Micro-AB connectors.

7.8. Audio

7.8.1. Micrófono

Device implementations MAY omit a microphone. However, if a device implementation omits a microphone, it MUST NOT report the android.hardware.microphone feature constant, and MUST implement the audio recording API at least as no-ops, per section 7 . Conversely, device implementations that do possess a microphone:

• MUST report the android.hardware.microphone feature constant
• MUST meet the audio recording requirements in section 5.4
• MUST meet the audio latency requirements in section 5.6
• STRONGLY RECOMMENDED to support near-ultrasound recording as described in section 7.8.3

7.8.2. Salida de audio

Device implementations including a speaker or with an audio/multimedia output port for an audio output peripheral as a headset or an external speaker:

• MUST report the android.hardware.audio.output feature constant.
• MUST meet the audio playback requirements in section 5.5 .
• MUST meet the audio latency requirements in section 5.6 .
• STRONGLY RECOMMENDED to support near-ultrasound playback as described in section 7.8.3

Conversely, if a device implementation does not include a speaker or audio output port, it MUST NOT report the android.hardware.audio output feature, and MUST implement the Audio Output related APIs as no-ops at least.

Android Watch device implementation MAY but SHOULD NOT have audio output, but other types of Android device implementations MUST have an audio output and declare android.hardware.audio.output.

7.8.2.1. Puertos de audio analógico

In order to be compatible with the headsets and other audio accessories using the 3.5mm audio plug across the Android ecosystem [ Resources, 122 ], if a device implementation includes one or more analog audio ports, at least one of the audio port(s) SHOULD be a 4 conductor 3.5mm audio jack. If a device implementation has a 4 conductor 3.5mm audio jack, it:

• MUST support audio playback to stereo headphones and stereo headsets with a microphone, and SHOULD support audio recording from stereo headsets with a microphone.
• MUST support TRRS audio plugs with the CTIA pin-out order, and SHOULD support audio plugs with the OMTP pin-out order.
• MUST support the detection of microphone on the plugged in audio accessory, if the device implementation supports a microphone, and broadcast the android.intent.action.HEADSET_PLUG with the extra value microphone set as 1.
• SHOULD support the detection and mapping to the keycodes for the following 3 ranges of equivalent impedance between the microphone and ground conductors on the audio plug:
  • 70 ohm or less : KEYCODE_HEADSETHOOK
  • 210-290 Ohm : KEYCODE_VOLUME_UP
  • 360-680 Ohm : KEYCODE_VOLUME_DOWN
• SHOULD support the detection and mapping to the keycode for the following range of equivalent impedance between the microphone and ground conductors on the audio plug:
  • 110-180 Ohm: KEYCODE_VOICE_ASSIST
• MUST trigger ACTION_HEADSET_PLUG upon a plug insert, but only after all contacts on plug are touching their relevant segments on the jack.
• MUST be capable of driving at least 150mV ± 10% of output voltage on a 32 Ohm speaker impedance.
• MUST have a microphone bias voltage between 1.8V ~ 2.9V.

7.8.3. Near-Ultrasound

Near-Ultrasound audio is the 18.5 kHz to 20 kHz band. Device implementations MUST correctly report the support of near-ultrasound audio capability via the AudioManager.getProperty API as follows:

• If PROPERTY_SUPPORT_MIC_NEAR_ULTRASOUND is "true", then
  • The microphone's mean power response in the 18.5 kHz to 20 kHz band MUST be no more than 15 dB below the response at 2 kHz.
  • The microphone's unweighted signal-to-noise ratio (SNR) over 18.5 kHz to 20 kHz for a 19 kHz tone at -26 dBFS MUST be no lower than 50 dB.
• If PROPERTY_SUPPORT_SPEAKER_NEAR_ULTRASOUND is "true", then the speaker's mean response in 18.5 kHz - 20 kHz MUST be no lower than 40 dB below the response at 2 kHz.

8. Performance and Power

Some minimum performance and power criteria are critical to the user experience and impact the baseline assumptions developers would have when developing an app. Android Watch devices SHOULD and other type of device implementations MUST meet the following criteria:

8.1. User Experience Consistency

Device implementations MUST provide a smooth user interface by ensuring a consistent frame rate and response times for applications and games. Device implementations MUST meet the following requirements:

• Consistent frame latency . Inconsistent frame latency or a delay to render frames MUST NOT happen more often than 5 frames in a second, and SHOULD be below 1 frames in a second.
• User interface latency . Device implementations MUST ensure low latency user experience by scrolling a list of 10K list entries as defined by the Android Compatibility Test Suite (CTS) in less than 36 secs.
• Cambiar de tarea . When multiple applications have been launched, re-launching an already-running application after it has been launched MUST take less than 1 second.

8.2. File I/O Access Performance

Device implementations MUST ensure internal storage file access performance consistency for read and write operations.

• Sequential write . Device implementations MUST ensure a sequential write performance of at least 5MB/s for a 256MB file using 10MB write buffer.
• Random write . Device implementations MUST ensure a random write performance of at least 0.5MB/s for a 256MB file using 4KB write buffer.
• Sequential read . Device implementations MUST ensure a sequential read performance of at least 15MB/s for a 256MB file using 10MB write buffer.
• Random read . Device implementations MUST ensure a random read performance of at least 3.5MB/s for a 256MB file using 4KB write buffer.

8.3. Modos de ahorro de energía

All apps exempted from App Standby and/or Doze mode MUST be made visible to the end user. Further, the triggering, maintenance, wakeup algorithms and the use of Global system settings of these power-saving modes MUST not deviate from the Android Open Source Project.

8.4. Power Consumption Accounting

A more accurate accounting and reporting of the power consumption provides the app developer both the incentives and the tools to optimize the power usage pattern of the application. Therefore, device implementations:

• MUST be able to track hardware component power usage and attribute that power usage to specific applications. Specifically, implementations:
  • MUST provide a per-component power profile that defines the current consumption value for each hardware component and the approximate battery drain caused by the components over time as documented in the Android Open Source Project site [ Resources, 123 ].
  • MUST report all power consumption values in milliampere hours (mAh)
  • SHOULD be attributed to the hardware component itself if unable to attribute hardware component power usage to an application.
  • MUST report CPU power consumption per each process's UID. The Android Open Source Project meets the requirement through the uid_cputime kernel module implementation.
• MUST make this power usage available via the adb shell dumpsys batterystats shell command to the app developer [ Resources, 124 ].
• MUST honor the android.intent.action.POWER_USAGE_SUMMARY intent and display a settings menu that shows this power usage [ Resources, 125 ].

9. Security Model Compatibility

Device implementations MUST implement a security model consistent with the Android platform security model as defined in Security and Permissions reference document in the APIs [ Resources, 126 ] in the Android developer documentation. Device implementations MUST support installation of self-signed applications without requiring any additional permissions/certificates from any third parties/authorities. Specifically, compatible devices MUST support the security mechanisms described in the follow subsections.

9.1. Permisos

Device implementations MUST support the Android permissions model as defined in the Android developer documentation [ Resources, 126 ]. Specifically, implementations MUST enforce each permission defined as described in the SDK documentation; no permissions may be omitted, altered, or ignored. Implementations MAY add additional permissions, provided the new permission ID strings are not in the android.* namespace.

Permissions with a protection level of dangerous are runtime permissions. Applications with targetSdkVersion > 22 request them at runtime. Implementaciones de dispositivos:

• MUST show a dedicated interface for the user to decide whether to grant the requested runtime permissions and also provide an interface for the user to manage runtime permissions.
• MUST have one and only one implementation of both user interfaces.
• MUST NOT grant any runtime permissions to preinstalled apps unless:
  • the user's consent can be obtained before the application uses it
  • the runtime permissions are associated with an intent pattern for which the preinstalled application is set as the default handler

9.2. UID and Process Isolation

Device implementations MUST support the Android application sandbox model, in which each application runs as a unique Unixstyle UID and in a separate process. Device implementations MUST support running multiple applications as the same Linux user ID, provided that the applications are properly signed and constructed, as defined in the Security and Permissions reference [ Resources, 126 ].

9.3. Permisos del sistema de archivos

Device implementations MUST support the Android file access permissions model as defined in the Security and Permissions reference [ Resources, 126 ].

9.4. Alternate Execution Environments

Device implementations MAY include runtime environments that execute applications using some other software or technology than the Dalvik Executable Format or native code. However, such alternate execution environments MUST NOT compromise the Android security model or the security of installed Android applications, as described in this section.

Alternate runtimes MUST themselves be Android applications, and abide by the standard Android security model, as described elsewhere in section 9 .

Alternate runtimes MUST NOT be granted access to resources protected by permissions not requested in the runtime's AndroidManifest.xml file via the <uses-permission> mechanism.

Alternate runtimes MUST NOT permit applications to make use of features protected by Android permissions restricted to system applications.

Alternate runtimes MUST abide by the Android sandbox model. Specifically, alternate runtimes:

• SHOULD install apps via the PackageManager into separate Android sandboxes ( Linux user IDs, etc.).
• MAY provide a single Android sandbox shared by all applications using the alternate runtime.
• and installed applications using an alternate runtime, MUST NOT reuse the sandbox of any other app installed on the device, except through the standard Android mechanisms of shared user ID and signing certificate.
• MUST NOT launch with, grant, or be granted access to the sandboxes corresponding to other Android applications.
• MUST NOT be launched with, be granted, or grant to other applications any privileges of the superuser (root), or of any other user ID.

The .apk files of alternate runtimes MAY be included in the system image of a device implementation, but MUST be signed with a key distinct from the key used to sign other applications included with the device implementation.

When installing applications, alternate runtimes MUST obtain user consent for the Android permissions used by the application. If an application needs to make use of a device resource for which there is a corresponding Android permission (such as Camera, GPS, etc.), the alternate runtime MUST inform the user that the application will be able to access that resource. If the runtime environment does not record application capabilities in this manner, the runtime environment MUST list all permissions held by the runtime itself when installing any application using that runtime.

9.5. Soporte multiusuario

Android includes support for multiple users and provides support for full user isolation [ Resources, 127 ]. Device implementations MAY enable multiple users, but when enabled MUST meet the following requirements related to multi-user support [ Resources, 128 ]:

• Device implementations that do not declare the android.hardware.telephony feature flag MUST support restricted profiles, a feature that allows device owners to manage additional users and their capabilities on the device. With restricted profiles, device owners can quickly set up separate environments for additional users to work in, with the ability to manage finer-grained restrictions in the apps that are available in those environments.
• Conversely device implementations that declare the android.hardware.telephony feature flag MUST NOT support restricted profiles but MUST align with the AOSP implementation of controls to enable /disable other users from accessing the voice calls and SMS.
• Device implementations MUST, for each user, implement a security model consistent with the Android platform security model as defined in Security and Permissions reference document in the APIs [ Resources, 126 ].
• Each user instance on an Android device MUST have separate and isolated external storage directories. Device implementations MAY store multiple users' data on the same volume or filesystem. However, the device implementation MUST ensure that applications owned by and running on behalf a given user cannot list, read, or write to data owned by any other user. Note that removable media, such as SD card slots, can allow one user to access another's data by means of a host PC. For this reason, device implementations that use removable media for the primary external storage APIs MUST encrypt the contents of the SD card if multiuser is enabled using a key stored only on non-removable media accessible only to the system. As this will make the media unreadable by a host PC, device implementations will be required to switch to MTP or a similar system to provide host PCs with access to the current user's data. Accordingly, device implementations MAY but SHOULD NOT enable multi-user if they use removable media [ Resources, 129 ] for primary external storage.

9.6. Premium SMS Warning

Android includes support for warning users of any outgoing premium SMS message [ Resources, 130 ]. Premium SMS messages are text messages sent to a service registered with a carrier that may incur a charge to the user. Device implementations that declare support for android.hardware.telephony MUST warn users before sending a SMS message to numbers identified by regular expressions defined in /data/misc/sms/codes.xml file in the device. The upstream Android Open Source Project provides an implementation that satisfies this requirement.

9.7. Kernel Security Features

The Android Sandbox includes features that use the Security-Enhanced Linux (SELinux) mandatory access control (MAC) system and other security features in the Linux kernel. SELinux or any other security features implemented below the Android framework:

• MUST maintain compatibility with existing applications.
• MUST NOT have a visible user interface when a security violation is detected and successfully blocked, but MAY have a visible user interface when an unblocked security violation occurs resulting in a successful exploit.
• SHOULD NOT be user or developer configurable.

If any API for configuration of policy is exposed to an application that can affect another application (such as a Device Administration API), the API MUST NOT allow configurations that break compatibility.

Devices MUST implement SELinux or, if using a kernel other than Linux, an equivalent mandatory access control system. Devices MUST also meet the following requirements, which are satisfied by the reference implementation in the upstream Android Open Source Project.

Implementaciones de dispositivos:

• MUST set SELinux to global enforcing mode.
• MUST configure all domains in enforcing mode. No permissive mode domains are allowed, including domains specific to a device/vendor.
• MUST NOT modify, omit, or replace the neverallow rules present within the external/sepolicy folder provided in the upstream Android Open Source Project (AOSP) and the policy MUST compile with all neverallow rules present, for both AOSP SELinux domains as well as device/vendor specific domains.

Device implementations SHOULD retain the default SELinux policy provided in the external/sepolicy folder of the upstream Android Open Source Project and only further add to this policy for their own device-specific configuration. Device implementations MUST be compatible with the upstream Android Open Source Project.

9.8. Privacidad

If the device implements functionality in the system that captures the contents displayed on the screen and/or records the audio stream played on the device, it MUST continuously notify the user whenever this functionality is enabled and actively capturing/recording.

If a device implementation has a mechanism that routes network data traffic through a proxy server or VPN gateway by default (for example, preloading a VPN service with android.permission.CONTROL_VPN granted), the device implementation MUST ask for the user's consent before enabling that mecanismo.

If a device implementation has a USB port with USB peripheral mode support, it MUST present a user interface asking for the user's consent before allowing access to the contents of the shared storage over the USB port.

9.9. Cifrado de disco completo

If the device implementation supports a secure lock screen reporting " true " for KeyguardManager.isDeviceSecure() [ Resources, 131 ], and is not a device with restricted memory as reported through the ActivityManager.isLowRamDevice() method, then the device MUST support full-disk encryption [ Resources, 132 ] of the application private data (/data partition), as well as the application shared storage partition (/sdcard partition) if it is a permanent, non-removable part of the device.

For device implementations supporting full-disk encryption and with Advanced Encryption Standard (AES) crypto performance above 50MiB/sec, the full-disk encryption MUST be enabled by default at the time the user has completed the out-of-box setup experience. If a device implementation is already launched on an earlier Android version with full-disk encryption disabled by default, such a device cannot meet the requirement through a system software update and thus MAY be exempted.

Encryption MUST use AES with a key of 128-bits (or greater) and a mode designed for storage (for example, AES-XTS, AES-CBC-ESSIV). The encryption key MUST NOT be written to storage at any time without being encrypted. Other than when in active use, the encryption key SHOULD be AES encrypted with the lockscreen passcode stretched using a slow stretching algorithm (eg PBKDF2 or scrypt). If the user has not specified a lockscreen passcode or has disabled use of the passcode for encryption, the system SHOULD use a default passcode to wrap the encryption key. If the device provides a hardware-backed keystore, the password stretching algorithm MUST be cryptographically bound to that keystore. The encryption key MUST NOT be sent off the device (even when wrapped with the user passcode and/or hardware bound key). The upstream Android Open Source project provides a preferred implementation of this feature based on the Linux kernel feature dm-crypt.

9.10. Arranque verificado

Verified boot is a feature that guarantees the integrity of the device software. If a device implementation supports the feature, it MUST:

• Declare the platform feature flag android.software.verified_boot
• Perform verification on every boot sequence
• Start verification from an immutable hardware key that is the root of trust, and go all the way up to the system partition
• Implement each stage of verification to check the integrity and authenticity of all the bytes in the next stage before executing the code in the next stage
• Use verification algorithms as strong as current recommendations from NIST for hashing algorithms (SHA-256) and public key sizes (RSA-2048)

The upstream Android Open Source Project provides a preferred implementation of this feature based on the Linux kernel feature dm-verity.

Starting from Android 6.0, device implementations with Advanced Encryption Standard (AES) crypto performance above 50MiB/seconds MUST support verified boot for device integrity. If a device implementation is already launched without supporting verified boot on an earlier version of Android, such a device can not add support for this feature with a system software update and thus are exempted from the requirement.

9.11. Keys and Credentials

The Android Keystore System [ Resources, 133 ] allows app developers to store cryptographic keys in a container and use them in cryptographic operations through the KeyChain API [ Resources, 134 ] or the Keystore API [ Resources, 135 ].

All Android device implementations MUST meet the following requirements:

• SHOULD not limit the number of keys that can be generated, and MUST at least allow more than 8,192 keys to be imported.
• The lock screen authentication MUST rate limit attempts and SHOULD have an exponential backoff algorithm as implemented in the Android Open Source Project.
• When the device implementation supports a secure lock screen and has a secure hardware such as a Secure Element (SE) where a Trusted Execution Environment (TEE) can be implemented, then it:
  • Is STRONGLY RECOMMENDED to back up the keystore implementation with the secure hardware. The upstream Android Open Source Project provides the Keymaster Hardware Abstraction Layer (HAL) implementation that can be used to satisfy this requirement.
  • MUST perform the lock screen authentication in the secure hardware if the device has a hardware-backed keystore implementation and only when successful allow the authentication-bound keys to be used. The upstream Android Open Source Project provides the Gatekeeper Hardware Abstraction Layer (HAL) that can be used to satisfy this requirement [ Resources, 136 ].

Note that while the above TEE-related requirements are stated as STRONGLY RECOMMENDED, the Compatibility Definition for the next API version is planned to changed these to REQUIRED. If a device implementation is already launched on an earlier Android version and has not implemented a trusted operating system on the secure hardware, such a device might not be able to meet the requirements through a system software update and thus is STRONGLY RECOMMENDED to implement a TEE .

9.12. Eliminación de datos

Devices MUST provide users with a mechanism to perform a "Factory Data Reset" that allows logical and physical deletion of all data except for the system image and data in other partitions that can be regarded as part of the system image. This MUST satisfy relevant industry standards for data deletion such as NIST SP800-88. This MUST be used for the implementation of the wipeData() API (part of the Android Device Administration API) described in section 3.9 Device Administration .

Devices MAY provide a fast data wipe that conducts a logical data erase.

10. Software Compatibility Testing

Device implementations MUST pass all tests described in this section.

However, note that no software test package is fully comprehensive. For this reason, device implementers are STRONGLY RECOMMENDED to make the minimum number of changes as possible to the reference and preferred implementation of Android available from the Android Open Source Project. This will minimize the risk of introducing bugs that create incompatibilities requiring rework and potential device updates.

10.1. Compatibility Test Suite

Device implementations MUST pass the Android Compatibility Test Suite (CTS) [ Resources, 137 ] available from the Android Open Source Project, using the final shipping software on the device. Additionally, device implementers SHOULD use the reference implementation in the Android Open Source tree as much as possible, and MUST ensure compatibility in cases of ambiguity in CTS and for any reimplementations of parts of the reference source code.

The CTS is designed to be run on an actual device. Like any software, the CTS may itself contain bugs. The CTS will be versioned independently of this Compatibility Definition, and multiple revisions of the CTS may be released for Android 6.0. Device implementations MUST pass the latest CTS version available at the time the device software is completed.

10.2. CTS Verifier

Device implementations MUST correctly execute all applicable cases in the CTS Verifier. The CTS Verifier is included with the Compatibility Test Suite, and is intended to be run by a human operator to test functionality that cannot be tested by an automated system, such as correct functioning of a camera and sensors.

The CTS Verifier has tests for many kinds of hardware, including some hardware that is optional. Device implementations MUST pass all tests for hardware that they possess; for instance, if a device possesses an accelerometer, it MUST correctly execute the Accelerometer test case in the CTS Verifier. Test cases for features noted as optional by this Compatibility Definition Document MAY be skipped or omitted.

Every device and every build MUST correctly run the CTS Verifier, as noted above. However, since many builds are very similar, device implementers are not expected to explicitly run the CTS Verifier on builds that differ only in trivial ways. Specifically, device implementations that differ from an implementation that has passed the CTS Verifier only by the set of included locales, branding, etc. MAY omit the CTS Verifier test.

11. Updatable Software

Device implementations MUST include a mechanism to replace the entirety of the system software. The mechanism need not perform “live” upgrades—that is, a device restart MAY be required.

Any method can be used, provided that it can replace the entirety of the software preinstalled on the device. For instance, any of the following approaches will satisfy this requirement:

• “Over-the-air (OTA)” downloads with offline update via reboot
• “Tethered” updates over USB from a host PC
• “Offline” updates via a reboot and update from a file on removable storage

However, if the device implementation includes support for an unmetered data connection such as 802.11 or Bluetooth PAN (Personal Area Network) profile:

• Android Automotive implementations SHOULD support OTA downloads with offline update via reboot.
• All other device implementations MUST support OTA downloads with offline update via reboot.

The update mechanism used MUST support updates without wiping user data. That is, the update mechanism MUST preserve application private data and application shared data. Note that the upstream Android software includes an update mechanism that satisfies this requirement.

For device implementations that are launching with Android 6.0 and later, the update mechanism SHOULD support verifying that the system image is binary identical to expected result following an OTA. The block-based OTA implementation in the upstream Android Open Source Project, added since Android 5.1, satisfies this requirement.

If an error is found in a device implementation after it has been released but within its reasonable product lifetime that is determined in consultation with the Android Compatibility Team to affect the compatibility of third-party applications, the device implementer MUST correct the error via a software update available that can be applied per the mechanism just described.

Android includes features that allow the Device Owner app (if present) to control the installation of system updates. To facilitate this, the system update subsystem for devices that report android.software.device_admin MUST implement the behavior described in the SystemUpdatePolicy class [ Resources, 138 ].

12. Document Changelog

The following table contains a summary of the changes to the Compatibility Definition in this release.

Sección	Resumen de Cambios
Varios	Replaced instances of the "encouraged" term with "RECOMMENDED"
2. Device Types	Update for Android Automotive implementations
3.2.2. Parámetros de construcción	Additions for the hardware serial number and for the security patch level of a build
3.2.3.2. Resolución de intención	Section renamed from "Intent Overrides" to "Intent Resolution," with new requirements related to authoritative default app linking
3.3.1. Interfaces binarias de aplicaciones	Additions for Android ABI support; change related to Vulkan library name
3.4.1. WebView Compatibility	Change for the user agent string reported by the WebView
3.7. Runtime Compatibility	Updates to memory allocation table
3.8.4. Buscar	Updates regarding Assistant requirements
3.8.6. Temas	Added requirement to support black system icons when requested by the SYSTEM_UI_FLAG_LIGHT_STATUS_BAR flag
3.8.8. Activity Switching	Relaxed Overview title count requirement.
3.8.10. Lock Screen Media Control	Lock Screen Media Control to refer to 3.8.3 in detail.
3.9.1. Aprovisionamiento de dispositivos	Contains new sections for device owner provisioning and managed profile provisioning
3.9.2. Managed Profile Support	New section with requirements for device support of managed profile functionality
3.12.1. Aplicación de televisión	Added section to clarify TV App requirements for Android Television devices
3.12.1.1. Electronic Program Guide	Added section to clarify EPG requirements for Android Television devices
3.12.1.2. Navegación	Added section to clarify TV App navigation requirements for Android Television devices
3.12.1.3. TV input app linking	Added section to clarify TV input app linking support requirements for Android Television devices
5.1. Media Codecs	Updates regarding support for core media formats and decoding.
5.1.3. Códecs de vídeo	Changes and additions related to Android Televisions
5.2. Codificación de vídeo	Changes for encoders
5.3. Decodificación de vídeo	Changes for decoders, including regarding support for dynamic video resolution, frame rate switching, and more
5.4. Grabación de audio	Additions related to audio capture
5.6. Latencia de audio	Update regarding reporting of support for low-latency audio
5.10. Audio profesional	General updates for professional audio support; updates for mobile device (jack) specifications, USB audio host mode, and other updates
5.9. Interfaz digital para instrumentos musicales (MIDI)	Added new section on optional Musical Instrument Digital Interface (MIDI) support
6.1. Herramientas de desarrollo	Update for drivers supporting Windows 10
7.1.1.3. Densidad de la pantalla	Updates for screen density, for example related to an Android watch
7.2.3. Teclas de navegación	Updated requirements for device implementations that include the Assist action
7.3. Sensors (and subsections)	New requirements for some sensor types
7.3.9. High Fidelity Sensors	New section with requirements for devices supporting high fidelity sensors
7.3.10. Sensor de huellas dactilares	New section on requirements related to fingerprint sensors
7.4.2. IEEE 802.11 (Wi-Fi)	Updates regarding support for multicast DNS (mDNS)
7.4.3. Bluetooth	Addition related to Resolvable Private Address (RPA) for Bluetooth Low Energy (BLE)
7.4.4. Comunicaciones de campo cercano	Additions to requirements for Near-Field Communications (NFC)
7.4.5. Minimum Network Capability	Added requirements for IPv6 support
7.6.3. Almacenamiento adoptable	New section for implementation of adoptable storage
7.7. USB	Requirement related to implementing the AOA specification
7.8.3. Near-Ultrasound	Additions related to near-ultrasound recording, playback, and audio	Relax Near-ultrasound microphone SNR requirement.
8.3. Modos de ahorro de energía	New section with requirements regarding the App Standby and Doze modes
8.4. Power Consumption Accounting	New section with requirements for tracking hardware component power usage and attributing that power usage to specific applications
9.1. Permisos	Addition to Permissions requirements
9.7. Kernel Security Features	SE Linux updates
9.8. Privacidad	Addition regarding user's consent for access to shared storage over a USB port
9.9. Cifrado de disco completo	Requirements related to full disk encryption
9.10. Arranque verificado	Additional requirement for verified boot
9.11. Keys and Credentials	New section of requirements related to keys and credentials
9.12. Eliminación de datos	New section for "Factory Data Reset"
11. Updatable Software	Requirement related to the system update policy set by the device owner

13. Contáctenos

You can join the android-compatibility forum [Resources, 139 ] and ask for clarifications or bring up any issues that you think the document does not cover.

14. Recursos

1. IETF RFC2119 Requirement Levels: http://www.ietf.org/rfc/rfc2119.txt

2. Android Open Source Project: http://source.android.com/

3. Android Television features: http://developer.android.com/reference/android/content/pm/PackageManager.html#FEATURE_LEANBACK

4. Android Watch feature: http://developer.android.com/reference/android/content/res/Configuration.html#UI_MODE_TYPE_WATCH

5. Android UI_MODE_TYPE_CAR API: http://developer.android.com/reference/android/content/res/Configuration.html#UI_MODE_TYPE_CAR

6. API definitions and documentation: http://developer.android.com/reference/packages.html

7. Android Permissions reference: http://developer.android.com/reference/android/Manifest.permission.html

8. android.os.Build reference: http://developer.android.com/reference/android/os/Build.html

9. Android 6.0 allowed version strings: http://source.android.com/docs/compatibility/6.0/versions.html

10. Android Developer Settings: http://developer.android.com/reference/android/provider/Settings.html

11. Telephony Provider: http://developer.android.com/reference/android/provider/Telephony.html

12. Android NDK ABI Management: https://developer.android.com/ndk/guides/abis.html

13. Advanced SIMD architecture: http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0388f/Beijfcja.html

14. Android Extension Pack: http://developer.android.com/guide/topics/graphics/opengl.html#aep

15. android.webkit.WebView class: http://developer.android.com/reference/android/webkit/WebView.html

16. WebView compatibility: http://www.chromium.org/

17. HTML5: http://html.spec.whatwg.org/multipage/

18. HTML5 offline capabilities: http://dev.w3.org/html5/spec/Overview.html#offline

19. HTML5 video tag: http://dev.w3.org/html5/spec/Overview.html#video

20. HTML5/W3C geolocation API: http://www.w3.org/TR/geolocation-API/

21. HTML5/W3C webstorage API: http://www.w3.org/TR/webstorage/

22. HTML5/W3C IndexedDB API: http://www.w3.org/TR/IndexedDB/

23. Dalvik Executable Format and bytecode specification: available in the Android source code, at dalvik/docs

24. AppWidgets: http://developer.android.com/guide/practices/ui_guidelines/widget_design.html

25. Notifications: http://developer.android.com/guide/topics/ui/notifiers/notifications.html

26. Application Resources: https://developer.android.com/guide/topics/resources/available-resources.html

27. Status Bar icon style guide: http://developer.android.com/design/style/iconography.html

28. Notifications Resources: https://developer.android.com/design/patterns/notifications.html

29. Search Manager: http://developer.android.com/reference/android/app/SearchManager.html

30. Action Assist: http://developer.android.com/reference/android/content/Intent.html#ACTION_ASSIST

31. Android Assist APIs: https://developer.android.com/reference/android/app/assist/package-summary.html

32. Toasts: http://developer.android.com/reference/android/widget/Toast.html

33. Themes: http://developer.android.com/guide/topics/ui/themes.html

34. R.style class: http://developer.android.com/reference/android/R.style.html

35. Material design: http://developer.android.com/reference/android/R.style.html#Theme_Material

36. Live Wallpapers: http://developer.android.com/reference/android/service/wallpaper/WallpaperService.html

37. Overview screen resources: http://developer.android.com/guide/components/recents.html

38. Screen pinning: https://developer.android.com/about/versions/android-5.0.html#ScreenPinning

39. Input methods: http://developer.android.com/guide/topics/text/creating-input-method.html

40. Media Notification: https://developer.android.com/reference/android/app/Notification.MediaStyle.html

41. Dreams: http://developer.android.com/reference/android/service/dreams/DreamService.html

42. Settings.Secure LOCATION_MODE: http://developer.android.com/reference/android/provider/Settings.Secure.html#LOCATION_MODE

43. Unicode 6.1.0: http://www.unicode.org/versions/Unicode6.1.0/

44. Android Device Administration: http://developer.android.com/guide/topics/admin/device-admin.html

45. DevicePolicyManager reference: http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html

46. Device Owner App: http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isDeviceOwnerApp(java.lang.String)

47. Android Device Owner Provisioning Flow: http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#ACTION_PROVISION_MANAGED_DEVICE

48. Device Owner Provisioning via NFC: /devices/tech/admin/provision.html#device_owner_provisioning_via_nfc

49. Android Profile Owner App: http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isProfileOwnerApp(java.lang.String)

50. Android Managed Profile Provisioning flow: http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#ACTION_PROVISION_MANAGED_PROFILE

51. Android Accessibility Service APIs: http://developer.android.com/reference/android/accessibilityservice/AccessibilityService.html

52. Android Accessibility APIs: http://developer.android.com/reference/android/view/accessibility/package-summary.html

53. Eyes Free project: http://code.google.com/p/eyes-free

54. Text-To-Speech APIs: http://developer.android.com/reference/android/speech/tts/package-summary.html

55. Television Input Framework: /devices/tv/index.html

56. TV App channels: http://developer.android.com/reference/android/media/tv/TvContract.Channels.html

57. Third-party TV inputs: /devices/tv/index.html#third-party_input_example

58. TV inputs: /devices/tv/index.html#tv_inputs

59. TV channel EPG fields: https://developer.android.com/reference/android/media/tv/TvContract.Programs.html

60. TV input app linking: http://developer.android.com/reference/android/media/tv/TvContract.Channels.html#COLUMN_APP_LINK_INTENT_URI

61. Reference tool documentation (for adb, aapt, ddms, systrace): http://developer.android.com/tools/help/index.html

62. Android apk file description: http://developer.android.com/guide/components/fundamentals.html

63. Manifest files: http://developer.android.com/guide/topics/manifest/manifest-intro.html

64. Android Media Formats: http://developer.android.com/guide/appendix/media-formats.html

65. Android MediaCodecList API: http://developer.android.com/reference/android/media/MediaCodecList.html

66. Android CamcorderProfile API: http://developer.android.com/reference/android/media/CamcorderProfile.html

67. WebM project: http://www.webmproject.org/

68. RTC Hardware Coding Requirements: http://www.webmproject.org/hardware/rtc-coding-requirements/

69. AudioEffect API: http://developer.android.com/reference/android/media/audiofx/AudioEffect.html

70. Android android.content.pm.PackageManager class and Hardware Features List: http://developer.android.com/reference/android/content/pm/PackageManager.html

71. HTTP Live Streaming Draft Protocol: http://tools.ietf.org/html/draft-pantos-http-live-streaming-03

72. ADB: http://developer.android.com/tools/help/adb.html

73. Dumpsys: /devices/input/diagnostics.html

74. DDMS: http://developer.android.com/tools/debugging/ddms.html

75. Monkey testing tool: http://developer.android.com/tools/help/monkey.html

76. SysyTrace tool: http://developer.android.com/tools/help/systrace.html

77. Android Application Development-Related Settings: http://developer.android.com/reference/android/provider/Settings.html#ACTION_APPLICATION_DEVELOPMENT_SETTINGS

78. Supporting Multiple Screens: http://developer.android.com/guide/practices/screens_support.html

79. android.util.DisplayMetrics: http://developer.android.com/reference/android/util/DisplayMetrics.html

80. RenderScript: http://developer.android.com/guide/topics/renderscript/

81. Android extension pack for OpenGL ES: https://developer.android.com/reference/android/opengl/GLES31Ext.html

82. Hardware Acceleration: http://developer.android.com/guide/topics/graphics/hardware-accel.html

83. EGL Extension-EGL_ANDROID_RECORDABLE: http://www.khronos.org/registry/egl/extensions/ANDROID/EGL_ANDROID_recordable.txt

84. Display Manager: http://developer.android.com/reference/android/hardware/display/DisplayManager.html

85. android.content.res.Configuration: http://developer.android.com/reference/android/content/res/Configuration.html

86. Touch Input Configuration: http://source.android.com/docs/core/interaction/input/touch-devices

87. Motion Event API: http://developer.android.com/reference/android/view/MotionEvent.html

88. Key Event API: http://developer.android.com/reference/android/view/KeyEvent.html

89. Android Open Source sensors: http://source.android.com/docs/core/interaction/sensors

90. android.hardware.SensorEvent: http://developer.android.com/reference/android/hardware/SensorEvent.html

91. Timestamp sensor event: http://developer.android.com/reference/android/hardware/SensorEvent.html#timestamp

92. Android Open Source composite sensors: /docs/core/interaction/sensors/sensor-types#composite_sensor_type_summary

93. Continuous trigger mode: http://developer.android.com/reference/android/hardware/Sensor.html#TYPE_ACCELEROMETER

95. Android Fingerprint API: https://developer.android.com/reference/android/hardware/fingerprint/package-summary.html

96. Android Fingerprint HAL: /devices/tech/security/authentication/fingerprint-hal.html

97. Wi-Fi Multicast API: http://developer.android.com/reference/android/net/wifi/WifiManager.MulticastLock.html

98. Wi-Fi Direct (Wi-Fi P2P): http://developer.android.com/reference/android/net/wifi/p2p/WifiP2pManager.html

99. WifiManager API: http://developer.android.com/reference/android/net/wifi/WifiManager.html

100. Bluetooth API: http://developer.android.com/reference/android/bluetooth/package-summary.html

101. Bluetooth ScanFilter API: https://developer.android.com/reference/android/bluetooth/le/ScanFilter.html

102. NFC Barcode: http://developer.android.com/reference/android/nfc/tech/NfcBarcode.html

103. NDEF Push Protocol: http://source.android.com/docs/compatibility/ndef-push-protocol.pdf

104. Android Beam: http://developer.android.com/guide/topics/connectivity/nfc/nfc.html

105. Android NFC Sharing Settings: http://developer.android.com/reference/android/provider/Settings.html#ACTION_NFCSHARING_SETTINGS

106. NFC Connection Handover: http://members.nfc-forum.org/specs/spec_list/#conn_handover

107. Bluetooth Secure Simple Pairing Using NFC: http://members.nfc-forum.org/apps/group_public/download.php/18688/NFCForum-AD-BTSSP_1_1.pdf

108. Host-based Card Emulation: http://developer.android.com/guide/topics/connectivity/nfc/hce.html

109. Content Resolver: http://developer.android.com/reference/android/content/ContentResolver.html

110. Camera orientation API: http://developer.android.com/reference/android/hardware/Camera.html#setDisplayOrientation(int)

111. Camera: http://developer.android.com/reference/android/hardware/Camera.html

112. Camera: http://developer.android.com/reference/android/hardware/Camera.Parameters.html

113. Camera hardware level: https://developer.android.com/reference/android/hardware/camera2/CameraCharacteristics.html#INFO_SUPPORTED_HARDWARE_LEVEL

114. Camera version support: http://source.android.com/docs/core/camera/versioning

115. Android DownloadManager: http://developer.android.com/reference/android/app/DownloadManager.html

116. Android File Transfer: http://www.android.com/filetransfer

117. Adoptable storage: http://source.android.com/docs/core/storage/adoptable

118. Android Open Accessories: http://developer.android.com/guide/topics/connectivity/usb/accessory.html

119. Android USB Audio: http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO

120. USB Battery Charging Specification, Revision 1.2: http://www.usb.org/developers/docs/devclass_docs/BCv1.2_070312.zip

121. USB Host API: http://developer.android.com/guide/topics/connectivity/usb/host.html

122. Wired audio headset: http://source.android.com/docs/core/interaction/accessories/headset/plug-headset-spec

123. Power profile components: http://source.android.com/docs/core/power/values

124. Batterystats: https://developer.android.com/tools/dumpsys#battery

125. Power usage summary: http://developer.android.com/reference/android/content/Intent.html#ACTION_POWER_USAGE_SUMMARY

126. Android Security and Permissions reference: http://developer.android.com/guide/topics/security/permissions.html

127. UserManager reference: http://developer.android.com/reference/android/os/UserManager.html

128. External Storage reference: http://source.android.com/docs/core/storage/traditional

129. External Storage APIs: http://developer.android.com/reference/android/os/Environment.html

130. SMS Short Code: http://en.wikipedia.org/wiki/Short_code

131. Secure lock screen reporting: http://developer.android.com/reference/android/app/KeyguardManager.html#isDeviceSecure()

132. Android Open Source Encryption: http://source.android.com/docs/security/features/encryption

133. Android Keystore System: https://developer.android.com/training/articles/keystore.html

134. KeyChain API: https://developer.android.com/reference/android/security/KeyChain.html

135. Keystore API: https://developer.android.com/reference/java/security/KeyStore.html

136. Gatekeeper HAL: http://source.android.com/docs/security/features/authentication/gatekeeper

137. Android Compatibility Program Overview: http://source.android.com/docs/compatibility

138. SystemUpdatePolicy class: http://developer.android.com/reference/android/app/admin/SystemUpdatePolicy.html

139. Android Compatibility forum: https://groups.google.com/forum/#!forum/android-compatibility

140. Handling app links: https://developer.android.com/training/app-links/index.html

141. Google Digital Asset Links: https://developers.google.com/digital-asset-links

Many of these resources are derived directly or indirectly from the Android SDK, and will be functionally identical to the information in that SDK's documentation. In any cases where this Compatibility Definition or the Compatibility Test Suite disagrees with the SDK documentation, the SDK documentation is considered authoritative. Any technical details provided in the references included above are considered by inclusion to be part of this Compatibility Definition.