Same issue here.
I try to get useful apps but I'm out of new ideas.
Some things I have/considered getting.
Tasker
Black screen of life (not available on google play anymore)
FoxFi key
Printershare key
Flightradar
Pdf scanner
Nova launcher
Artscroll seforim or some other type of e-judaica
Obd2 scanner app
Nostalgic games (although I haven't really played any )