I would personally recommend Glow Dots! Super simple, and one of the most addicting games I’ve played for Android. Also, Doodle Jump has been free for a few weeks, you might want to check that out! Tetris by EA is another great choice!
A good tip I’ve learned is that you hold the Volume Down button and the Lock button at the same time for a few seconds, you’ll take a screenshot of your display! Very helpful for the right instance!