It’s no secret that are iPad apps are a hot commodity right now. While most iPhone apps work on the iPad there really is no comparison to native iPad apps. They look better, and with iPad specific UI elements added they are better for the end user.
Ray Wenderlich, the creator of the Space Game Starter Kit and co-author of the Learning Cocos2D book, has written a great easy tutorial on porting an iPhone app to the iPad, that utilizes autosizing, and native iPad interface elements.
[Source: Ray Wenderlich]