Continuity 2 is another fun puzzle/platformer that the iPhone has inherited from Flash -- the original title also had you sliding various parts of puzzles around in order to get a little stick figure from one side of the level to the other. But Continuity 2 ups the ante, introducing new mechanics like switches, power sources that need to be hooked up to work, and even gravity flipping, sending your little guy caroming around the level while trying to reach the exit.
This game is everything a great puzzle game should be -- it offers up a number of simple mechanics, and then slowly tweaks up the complexity over time, asking you to constantly use the various mechanics in new and surprising ways. There are over 50 levels to play through, and full Game Center integration means if you want to, you'll be playing this one for a while.
Continuity 2: The Continuation is available on the iPhone as a universal app for just US 99 cents, or you can grab the lite version to check out the gameplay first if you'd rather do that. It is, however, an excellent puzzle game with lots of great ideas, so if that sounds like your thing, look it up.