Installing TWRP Recovery on the Google Asus Nexus 7 tablet will mean you can start flashing your custom kernels and custom ROMs. Custom kernels are great for overclocking a device and changing the internal system so the device runs better. A Custom ROM is great if you want more features, a different design, less bloatware and can also help with increased performance over a stock ROM. One feature that many forget with a custom recovery is the ability to take complete backups without having to use any adb commands from a computer.
- You must have the Asus Nexus 7 2012 edition to use this guide. Make sure yours is from that same year or else you will probably brick your Google tablet.
- You mist have adb set up on your computer so you can use the same to flash your custom recovery with the command line.
- You must have a Windows computer to use our tutorial or else you cannot set up adb with our guide.
BEFORE WE BEGIN
- Download the universal adb driver  on your Windows-based computer before you start the guide.
- Understand that you are voiding the Asus warranty when you go ahead and install a custom recovery on the Nexus 7 from 2012. You can always flash a stock recovery back over the top of your Asus tablet and the warranty will start working again. Just make sure you haven’t customized the device in any other way, or you will need to swap those back also. For example, anyone with a rooted Asus Nexus 7 tablet will also need to unroot before the warranty will work.
- Unlock the hidden Developer Options menu by tapping on the Menu > Settings > About Device > Build Number 7 times.
- Enable the USB Debugging Mode by tapping on the Menu > Settings > Developer Options > USB Debugging Mode.
HOW TO INSTALL TWRP RECOVERY ON ASUS NEXUS 7 2012 3G
- Learn how to set up adb  on your computer running Windows and then come back to this guide.
- Download the TWRP Recovery package for the Asus Nexus 7 from this link .
- Copy the TWRP Recovery file over to the same folder as your adb on the computer and leave the folder open.
- From within the same folder, hold down Shift and right-click the mouse where there are no files and choose to open a new command prompt window from the options on the menu.
- Connect the Asus Nexus 7 tablet to the computer with the USB cable.
- Type the first command in your command line:
adb reboot bootloader
- The Asus Nexus 7 2012 tablet will now be in fastboot mode.
- Type the next command to flash the custom recovery:
fastboot flash recovery twrp.img
- Type the final command to reboot the device:
Sometimes a device will replace the custom recovery with the stock recovery again during the first boot. You can fix that problem if it is happening to your Asus Nexus 7 by searching Google  for the right method to enter recovery mode on your device and holding that button combination when you are giving the “fastboot reboot” command.