A few days ago I decided to give my old Nexus 7 2013 (flo) a bit of a freshen up since it's a well enginered piece of kit and it deserved better than Android 6.01 I used TWRP to unlock and root the tablet and then looked around for suitable ROM code to upgrade. My initial thought was to go to Android 7 but then I found the Android 8.1 Oreo ROM here:
https://androidfilehost.com/?fid=1395089523397948526 and the corresponding Pico Gapps here:
https://androidfilehost.com/?fid=3700668719832236373 Along the way I had to update my TWRP software to fix the status error 7 --- see here:
https://android-fix.com/android-erro...or-7-twrp.html for one of the many descriptions of "How To". I now have an impressive Nexus 7 tablet that runs pretty much everything I throw at it. It runs Kindle well with super clarity and overall I'm happy to have given the tablet a new lease of life and look forward to reading many more books on it for some years to come.