What's a good, actually reliable iOS game to keep my brain a little active during those super long, you know, 12-hour shifts when I'm too tired to do anything else?

Okay, so I'm always looking for something simple that works when you need it, especially during those never-ending shifts at the clinic. I found Otium, and honestly, it's like having a pocket reference guide... for words, haha! It's just a word search game, nothing fancy, but it's actually reliable. I've been using it for about six months now, and it hasn't crashed once, which is a HUGE deal. I'm too tired to learn complicated apps, but this is super easy to pick up. Sometimes, between checking on patients and running around, it's nice to just zone out for a few minutes and find some words. It's a no-fuss approach, and honestly, that's exactly what I need after a long day. Plus, it kinda keeps your vocabulary on point, which is always a good thing, right?