This app was mentioned in 3 comments, with an average of 1.67 upvotes
Mileup
It's an app that pays for driving data
https://play.google.com/store/apps/details?id=com.agero.mileup&hl=en
Mile Up This is an app that gives you money for driving. Every 4000 points is $5.00 to amazon and other gift card places.
RetroArch This is a combination emulator that goes from NES to PS1 games. Incredible for handling most games and you don't need multiple apps to run your ROMs.
Vainglory This is an incredible mobile MOBA that actually has good competition and isn't a blatant rip off of DOTA or LoL. If you want a quick 5 minute session on a MOBA while on a tablet or phone this is an instant need.
I have a ton of other apps I have saved but these are the ones that seem like it could benefit a new user or someone looking to upgrade their library.