A series of games that are all about survival. Some are better than others.
Knightmare Tower (iOS)
With all the "forever runners" out there, it's hard to separate from the pack. And yet, Knightmare Tower does an excellent job, blending legit twitch gameplay and RPG mechanics with a high score chasing mentality. The Mad Magazine-esque art style doesn't hurt, either. This is a great game and an easy recommendation to make.
The Drowning (iOS)
The FPS genre has never fared too well on touch screens, so the developers of The Drowning tried a completely different control scheme, blending swipes and two-finger taps. Unfortunately the new control scheme doesn't seem to make things much more enjoyable, though if you are desperate and/or curious, the game is free-to-play, making it easy to try for yourself.
If you dug the jazzy survival elements of Super Hexagon, might I suggest Pivvot? The game starts off slow, but within a half-hour or so you'll unlock some of the more epic modes. It's speedy, with simple controls, which makes it ideal for commute gaming.