I am wanting to gain root privileges on my Google Nexus 7 tablet, running Android 4.1-4.2.1. How can I do this?
The Nexus 7 is probably one of the easiest Android devices to root - and all you need is the Android SDK (and 2 downloads).
fastboot commands. On Ubuntu:
sudo apt-get install android-tools-adb android-tools-fastboot
On Windows you should download the Android SDK, however you can just download this zip which contains the
fastboot and dependencies.
On your Nexus 7, go to
System Settings->Developer Options->Check USB Debugging (You may need to slide the toggle switch in the action bar to on). If you do not see the USB Debugging option, go to
System Settings->About Tablet->Tap on 'Build Number' 7 times.
Connect your Nexus to your computer.
Make sure the drivers have downloaded and installed if you're on Windows - Windows Update should automatically find them.
Once connected, open up a terminal window (Windows: Win+R, type
cmd press Enter. Ubuntu: ctrl+alt+t) and navigate to where you have unzipped the fastboot & adb programs (no need to do this on linux - they are in the path).
adb backup -all -nosystem to backup your userdata to the
adb reboot bootloader.
When the Nexus 7 has rebooted into fastboot mode, type
fastboot oem unlock. Read the information on the device, and touch the
Yes option. Your bootloader will be unlocked. This will erase all userdata!
Download the latest TWRP recovery image. Save it in the same location as the fastboot binary. Issue the
fastboot flash recovery twrp.img command to flash this recovery image.
From the fastboot menu (green robot on its back with the cover open), use the volume keys to cycle through the options
power off, to
recovery mode. Push the power key to select recovery mode.
You'll see the google logo with an unlocked padlock, and then the TWRP splash screen for about 45 seconds. Then TWRP asks "keep system read-only?" Instead of tapping on "no," swipe the swiper to allow these modifications.
This shows you the TWRP menu, 8 big buttons. Tap on
Advanced. On the next menu, tap on
Download the latest SuperSU zip file and save it to the same location as adb and fastboot. DON'T UNZIP IT.
On the Nexus 7, swipe the swiper to prepare it to sideload.
Issue the command
adb sideload CWM-SuperSU-v0.99.zip, which takes about a minute, and then tap the
reboot button. This may take several minutes and several reboots, so don't worry.
The Nexus 7 is now rooted!
adb restore <backup file made in 3.5> to restore from a backup.