The cube moves itself one face at a time, can speed up or slow down based on how you gesture, and can even climb itself up one level. It only takes a level or two to get the trick, and then the game really throws the hazards at you.
Finishing each level gets you a grade, that's based on how many glowing cubes you found and how few times you died.
Edge is an addictive puzzler with a stylish high-res interface and presentation that will also recall the Sony puzzle game Lumines. Finally, it seems as if most iPhone software contains bugs in the 1.0 version, so it's refreshing to see this one on its first version and apparently bug-free. Definitely recommended.