Doors is a game for Windows phone that will test your mind and powers of logical reasoning. The game presents you with a series of logic puzzles that you must solve in order to move forward.
Warning: this one's really going to test you.
Door has 40 levels, which we think is a little scant. That said, the game is a fun challenge and really makes you use all your senses to solve the puzzles. You're going to be racking your brains by the 7th level, and if you make it to 40, you'll have overcome some serious challenges.