We loved Nota, a piano learning app, on our iPhones. But we love the iPad version far more. Just look at how much better the iPad app looks when put right next to its iPhone counterpart:
As mentioned, it's not just about appearances when it comes to iPad apps and their iPhone counterparts. The additional screen real estate allows for a better feel, too:
The iPad version will have certain advantages over the iPhone version. For one, the much bigger size allows for a 2 octave piano comfortably. It also allows the design to be more like physical objects. The piano keys no longer go screen to screen, they are within a keyboard.
Of course, not all apps have a need to mimic real life objects like pianos, books, and similar. But the ones that do will certainly thrive on the iPad.[CNET]