Flashing Devices

This page provides details for running builds on specific devices. These details complement the information in Building Android.

Building fastboot and adb

If you don't already have fastboot and adb, you can build them with the regular build system. Use the instructions in Building Android and replace the main make command with this one:

make fastboot adb

See Android Debug Bridge (ADB) for details on Android Debug Bridge (ADB).

Booting into fastboot mode

You can flash a device when it's in the fastboot bootloader mode. To enter fastboot mode when a device is undergoing a cold boot, use the key combinations given in the table below.

You can also use the command adb reboot bootloader to reboot directly into the bootloader.

Device	Code name	Key combinations
Pixel 6 Pro	raven	Press and hold Volume Down, then press and hold Power.
Pixel 6	oriole	Press and hold Volume Down, then press and hold Power.
Pixel 5a (5G)	barbet	Press and hold Volume Down, then press and hold Power.
Pixel 5	redfin	Press and hold Volume Down, then press and hold Power.
Pixel 4a (5G)	bramble	Press and hold Volume Down, then press and hold Power.
Pixel 4a	sunfish	Press and hold Volume Down, then press and hold Power.
Pixel 4 XL	coral	Press and hold Volume Down, then press and hold Power.
Pixel 4	flame	Press and hold Volume Down, then press and hold Power.
Pixel 3a XL	bonito	Press and hold Volume Down, then press and hold Power.
Pixel 3a	sargo	Press and hold Volume Down, then press and hold Power.
Pixel 3 XL	crosshatch	Press and hold Volume Down, then press and hold Power.
Pixel 3	blueline	Press and hold Volume Down, then press and hold Power.
Pixel 2 XL	taimen	Press and hold Volume Down, then press and hold Power.
Pixel 2	walleye	Press and hold Volume Down, then press and hold Power.
Pixel XL	marlin	Press and hold Volume Down, then press and hold Power.
Pixel	sailfish	Press and hold Volume Down, then press and hold Power.
hikey	hikey	Link pins 1 - 2 and 5 - 6 of J15.
Nexus 6P	angler	Press and hold Volume Down, then press and hold Power.
Nexus 5X	bullhead	Press and hold Volume Down, then press and hold Power.
Nexus 6	shamu	Press and hold Volume Down, then press and hold Power.
Nexus Player	fugu	Press and hold Power.
Nexus 9	volantis	Press and hold Volume Down, then press and hold Power.
Nexus 5	hammerhead	Press and hold both Volume Up and Volume Down, then press and hold Power.
Nexus 7	flo	Press and hold Volume Down, then press and hold Power.
Nexus 7 3G	deb	Press and hold Volume Down, then press and hold Power.
Nexus 10	manta	Press and hold both Volume Up and Volume Down, then press and hold Power.
Nexus 4	mako	Press and hold Volume Down, then press and hold Power.
Nexus 7 (2012)	grouper	Press and hold Volume Down, then press and hold Power.
Nexus 7 3G (2012)	tilapia	Press and hold Volume Down, then press and hold Power.
Nexus Q	phantasm	Power the device then cover it with one hand after the LEDs light up and until they turn red.
Galaxy Nexus GSM	maguro	Press and hold both Volume Up and Volume Down, then press and hold Power.
Galaxy Nexus (Verizon)	toro	Press and hold both Volume Up and Volume Down, then press and hold Power.
Galaxy Nexus (Sprint)	toroplus	Press and hold both Volume Up and Volume Down, then press and hold Power.
Motorola Xoom	wingray	Press and hold Volume Down, then press and hold Power.
Nexus S	crespo	Press and hold Volume Up, then press and hold Power.
Nexus SG	crespo4g	Press and hold Volume Up, then press and hold Power.

Unlocking the bootloader

You can flash a custom system only if the bootloader allows it. Note, though, that the bootloader is locked by default. You can unlock the bootloader, but doing so deletes user data for privacy reasons. After unlocking, all data on the device is erased, that is, both private app data and shared data accessible over USB (including photos and movies). Before attempting to unlock the bootloader, back up any important files on the device.

You need to unlock the bootloader only once, and you can re-lock it if necessary.

Unlocking recent devices

All Nexus and Pixel devices released since 2014 (starting with Nexus 6 and Nexus 9) have factory-reset protection and require a multistep process to unlock the bootloader.

To enable OEM unlocking on the device:
1. In Settings, tap About phone, then tap Build number seven times.
2. When you see the message You are a developer, tap the back button.
3. Tap Developer options and enable OEM unlocking and USB debugging. (If OEM unlocking is disabled, connect to the internet so the device can check in at least once. If it remains disabled, your device might be SIM locked by your carrier and the bootloader can't be unlocked.)
Reboot into the bootloader and use fastboot to unlock it.
- For newer devices (2015 and higher):
```
fastboot flashing unlock
```
- For older devices (2014 and lower):
```
fastboot oem unlock
```
Confirm the unlock onscreen.

Note: On Nexus 10, after unlocking the bootloader, the internal storage remains unformatted. You can format the device using fastboot format cache followed by fastboot format userdata.

Re-locking the bootloader

To re-lock the bootloader:

For newer devices (2015 and higher):
```
fastboot flashing lock
```
For older devices (2014 and lower):
```
fastboot oem lock
```

Using flash lock states

The getFlashLockState() system API transmits the bootloader state and the PersistentDataBlockManager.getFlashLockState() system API returns the bootloader’s lock status on compliant devices.

Return value	Conditions
`FLASH_LOCK_UNKNOWN`	Returned only by devices upgrading to Android 7.x or higher that didn't previously support the bootloader changes required to get the flash lock status if they supported flashing lock/unlock capability. New devices running Android 7.x or higher must be in either a `FLASH_LOCK_LOCKED` or `FLASH_LOCK_UNLOCKED` state. Devices upgrading to Android 7.x or higher that don't support flashing unlock/lock capability should return a `FLASH_LOCK_LOCKED` state.
`FLASH_LOCK_LOCKED`	Returned by any device that doesn't support flashing lock/unlock (that is, the device is always locked), or any device that supports flashing lock/unlock and is in the locked state.
`FLASH_LOCK_UNLOCKED`	Returned by any device that supports flashing lock/unlock and is in the unlocked state.

Manufacturers should test the values returned by devices with locked and unlocked bootloaders. For an example, the Android Open Source Project (AOSP) contains a reference implementation that returns a value based on the ro.boot.flash.locked boot property. Example code is located in the following directories:

frameworks/base/services/core/java/com/android/server/PersistentDataBlockService.java
frameworks/base/core/java/android/service/persistentdata/PersistentDataBlockManager.java

Selecting a device build

The recommended device builds are available from the lunch menu, accessed when running the lunch command with no arguments. See Choosing a target for available build types and more information on the lunch command.

You can download factory images and binaries for Pixel and Nexus devices from developers.google.com. See Device binaries for downloads. For details and additional resources, see Obtaining proprietary binaries.

Device	Code name	Build configuration
Pixel 5	redfin	`aosp_redfin-userdebug`
Pixel 4a 5G	bramble	`aosp_bramble-userdebug`
Pixel 4a	sunfish	`aosp_sunfish-userdebug`
Pixel 4 XL	coral	`aosp_coral-userdebug`
Pixel 4	flame	`aosp_flame-userdebug`
Pixel 3a XL	bonito	`aosp_bonito-userdebug`
Pixel 3a	sargo	`aosp_sargo-userdebug`
Pixel 3 XL	crosshatch	`aosp_crosshatch-userdebug`
Pixel 3	blueline	`aosp_blueline-userdebug`
Pixel 2 XL	taimen	`aosp_taimen-userdebug`
Pixel 2	walleye	`aosp_walleye-userdebug`
Pixel XL	marlin	`aosp_marlin-userdebug`
Pixel	sailfish	`aosp_sailfish-userdebug`
HiKey	hikey	`hikey-userdebug`
Nexus 6P	angler	`aosp_angler-userdebug`
Nexus 5X	bullhead	`aosp_bullhead-userdebug`
Nexus 6	shamu	`aosp_shamu-userdebug`
Nexus Player	fugu	`aosp_fugu-userdebug`
Nexus 9	volantis (flounder)	`aosp_flounder-userdebug`
Nexus 5 (GSM/LTE)	hammerhead	`aosp_hammerhead-userdebug`
Nexus 7 (Wi-Fi)	razor (flo)	`aosp_flo-userdebug`
Nexus 7 (Mobile)	razorg (deb)	`aosp_deb-userdebug`
Nexus 10	mantaray (manta)	`full_manta-userdebug`
Nexus 4	occam (mako)	`full_mako-userdebug`
Nexus 7 (Wi-Fi)	nakasi (grouper)	`full_grouper-userdebug`
Nexus 7 (Mobile)	nakasig (tilapia)	`full_tilapia-userdebug`
Galaxy Nexus (GSM/HSPA+)	yakju (maguro)	`full_maguro-userdebug`
Galaxy Nexus (Verizon)	mysid (toro)	`√aosp_toro-userdebug`
Galaxy Nexus (Experimental)	mysidspr (toroplus)	`aosp_toroplus-userdebug`
Motorola Xoom (U.S. Wi-Fi)	wingray	`full_wingray-userdebug`
Nexus S	soju (crespo)	`full_crespo-userdebug`
Nexus S 4G	sojus (crespo4g)	`full_crespo4g-userdebug`

Flashing a device

You can flash an entire Android system in a single command; doing so verifies that the system being flashed is compatible with the installed bootloader and radio, writes the boot, recovery, and system partitions together, then reboots the system. Flashing also erases all user data, similarly to fastboot oem unlock.

To flash a device:

Place the device in fastboot mode by holding the appropriate key combination at boot or using the following command:
```
adb reboot bootloader
```
After the device is in fastboot mode, run:
```
fastboot flashall -w
```
The -w option wipes the /data partition on the device; this is useful for your first time flashing a particular device but is otherwise unnecessary.

Note: File systems created with fastboot on Motorola Xoom don't function optimally. The Android team recommends that you recreate file systems through recovery using $ adb reboot recovery. While in recovery, open the menu (press Power + Volume Up), wipe the cache partition, then wipe the data.

Restoring devices to factory state

Factory images for Google devices are available from Factory Images for Nexus and Pixel Devices. Factory images for the Motorola Xoom are distributed directly by Motorola.