What's a good Android game to keep my mind sharp with trivia that isn't just some boring textbook stuff?

So, I was looking for something to keep the old brain cells firing, you know? Something other than grading papers, ha! My student, Sarah, actually showed me this app called Trivia Spin－Guess Brain Quiz. Took me a few days to figure out all the features – why do they hide the settings button there? But once you get the hang of it, it's not bad at all. It's got a bunch of different trivia categories, so it's not just history dates or math problems (thank goodness!). It's got pop culture, science, even some sports stuff. I like that it makes you think a little, and it's a good way to unwind after a long day of teaching. Plus, it's something I can talk to the kids about – maybe even use some of the trivia in class as a little brain break. It's like having a teaching assistant in your pocket, but one that asks all the questions!