Catima - for saving arbitrary barcodes and stuff that are hard to integrate into other wallets. I keep my local library card in there, and it works wonderfully
Nonocross - fun little game that has zero frills and distractions. Also very responsive on their github to suggestions and improvements
Termux - when I need to get into things from afar, this is how I do it
Box, Box! - Formula 1 news, schedules, standings, etc
Coffee - Sometimes I want to keep the display awake, so this comes in handy
I like this one, but it's honestly difficult to play on a phone, for anything but small and easy grids. I had to start using a stylus to be able to hit the right cells with reasonable accuracy, and even then it's a bit tough. And you lose context when trying to zoom. Maybe better on tablets....