Yo, what's a good iOS game that'll keep my brain from turning to mush while I'm waiting for the damn walk-in to get fixed?

Look, I ain't got time for fancy BS. Most of these brain game apps are garbage, but Crossword Explorer? It's actually practical. It's got these crossword puzzles that are like mental mise en place – gets your head organized. I can bang out a few levels while I'm waiting for the fridge guy to show up, keeps me from yelling at the waitstaff. Plus, it's not all glitter and rainbows. It's straightforward, kitchen-tested, if you know what I mean. It's the kind of thing you can pick up and play even when your hands are covered in flour and you're sweating bullets 'cause dinner service is about to start. No time for hand-holding, just straight-up puzzle action. And that's what I need.