Are there any good trivia apps that aren’t just copies of Trivial Pursuit?
Have you tried Sporcle?
Not a game, but I enjoy just going to wikipedia’s app and hitting their random button to learn all sorts of random shit.
That’s always fun. You can make it a little more “gamey” by thinking of some person/place/thing of your choice, then hitting the random button and seeing how quickly you can get from the random page to the page you were thinking of by following links.