By now, you might already know a thing or nine about Android L, the latest version of Google’s mobile operating system. You may also know that developer previews for the Nexus 5 and Nexus 7 (2013) are now available to download and install. They're hardly in final form and not totally stable, but you can install them on your own accord, and I’m going to show you how.
Note: This method is relevant for installing any and all Android factory images from Google for Nexus phones or tablets. If you want to go back to another version of the OS, simply download the appropriate file from here and perform the same steps below!
- Have ADB and Fastboot set up properly (and know where these files on your computer are located!)
- Be willing to lose all data on your device. (Or check out this list of great backup apps beforehand.)
First up, head over to this link to download the Android L developer preview. The builds are named by the devices' code names: the code name for the Nexus 5 is Hammerhead and the Nexus 7 is Razor. After the file is finished downloading, extract it to your desktop for later use. The extracted file will be a folder named either hammerhead-lp79 or razor-lp79.
Now, find the folder that the ADB and Fastboot files currently reside in and open it. Open the folder your just extracted, highlight all of the files and drag them into the ADB folder.
Open a command window to your ADB folder by holding down the Shift button on your keyboard and right click on the open folder. Click on the Open command window here option. (On a Mac you'd use Terminal.)
Just to make sure everything is correctly setup, we’re going to run a few commands first.
In the command window, type in adb devices. The window should return List of attached devices with a combination of letters and numbers below it. (something like 01vu6m6633fgh39r device).
If you do not see this after typing adb devices, something is wrong and you won’t be able to continue until it is fixed. Assuming your device was found, type in the following command to boot your phone into bootloader mode: adb reboot bootloader
Give the phone a few seconds to boot into bootloader mode, and then type the following: flash-all.bat. This will begin the flashing process.
After a few minutes, your Nexus 5 or Nexus 7 will reboot. You’ll be presented with the new boot animation, and it may take a while to fully boot up, so give it some time. You’re good to go!
- Download file
- Move files into the same folder as ADB
- Open command window from ADB folder
- Connect phone: (test connection: adb devices)
- adb reboot bootloader