World of Goo

Either you've played World of Goo before, or you haven't. If you're in the latter category, it's time to pony up and join the club. An indie Game of the Year candidate when it first debuted as a downloadable game on the Nintendo Wii and PC, the iPad version is actually an improvement thanks to a shift to intuitive touch controls, as opposed to Wii remote-based gestures. A combination of construction toolkit and puzzle-platformer, World of Goo instantly rises to the top of our App Store must-buys.

Price: $4.99