What's a good Android game that's not just mindless tapping but actually makes you think, like, strategically?

Okay, so I'm always on the hunt for games that don't make me feel like I'm losing IQ points. Brain Test 3 is surprisingly good. It's got these tricky puzzles that aren't just about reflexes; you actually have to *think*. The solutions aren't always obvious, which is statistically satisfying. I mean, it's not going to replace my data analysis projects, but it's a decent way to kill time without turning my brain to mush. The puzzles are varied enough to keep things interesting, and the art style is clean and readable, which I appreciate. It's like a mental workout, but, you know, in a fun way. Plus, no excessive ads popping up every five seconds, which is a huge win in my book. Good clean datasets, good clean gameplay.