Your Nexus 7 can be updated to the non-official ROM namely Pure AOSP based on Android 6.0 Marshmallow that was designed to be as close as the stock firmware, thus you will experience nearly identical environment once this ROM it's installed as it's AOSP based ROM. And from the one who has reviewed this ROM saying that the Pure Marshmallow ROM is fast and stable enough. If you want to give this ROM a try.
Then follow the full instructions to flash it from here.
- Your device's bootloader must already be unlocked.
- Do not forget to firstly backup your device.
- Google has nothing to do with this Android custom ROM.
- Your device should already powered with a custom recovery, this post uses a CWM recovery.
- You will loose your device's warranty for installing this ROM.
- Your device's should be rooted already.
- This ROM doesn't come with Gapps, thus we will install the Gogole Apps separately, oke?
- Remember that this tutorial is only for Nexus 7.
Download the ROM zip file to your PC.
Instructions to flash Android 6.0 Marshmallow PURE AOSP ROM to Nexus 7.
- Connect your Nexus 7 to PC, then transfer the zip files you just downloaded, to your Nexus.
- Disconnect your Nexus after all the zip files transferred.
- Now shut down you Nexus 7 then boot into recovery mode.
- When you are in the recovery mode (CWM), then choose the Wipe Data/Factory Reset.
- After then choose Wipe Cache Partition continue to select Wipe Dalvik Cache. via Advanced mode.
- Now go on to select the Install Zip From SD Card -> Choose Zip From SD Card to further searching for the Pure AOSP ROM file to be installed on your Nexus 7.
- Repeat the process above to install GApps for your Nexus 7.
- When all the zip files flashed successfully then *****Go Back***** -> Reboot System Now.
- The Nexus 7 of yours will reboot now.
- Done my friend.