Hextris

This reminds me of one of the most frustrating/awesome games on the iPhone from a few years back: Super Hexagon

This got difficult way too quickly.

An incredibly simple but fun game. There are only two moves, rotate left and rotate right but that is enough to support what is very fun gameplay. My only complaint is that it gets pretty hard pretty quickly. Typically in games like this (e.g. tetris) the difficulty is slowly built up so that even novice players have at least a good five minutes of play before losing.