What's a good iOS game when I'm stuck on a job site waiting for materials and need to blow off some steam?

Alright, so look, I found this game called War Drone. It's no BS, gets the job done when you're stuck waiting for concrete to dry or something. You fly around in a drone, shooting stuff. Simple as that. The graphics are actually pretty good for a phone game; it's 3D, so you can see what you're doing. It's not gonna win any awards, but it's better than staring at a wall. The controls are easy enough to figure out, even with gloves on, though the tutorial is useless. Seriously, skip it. Just start blasting stuff, you'll figure it out. Only real downside is the battery drain. This thing sucks the juice out of your phone faster than a sandstorm in Arizona. Keep a charger handy, especially if you're out on a long job. But hey, for a free game, it's not bad. Definitely helps kill time.