I have a third generation iPad ("the New iPad"). I am looking for software I can use to make a piano keyboard appear on my iPad such that when I press the keys, they play notes and sound like a piano. I'd like to be able to use it to plunk out a tune when trying to compose music away from home, and to let my children practice their beginning piano lessons when we're visiting relatives but they don't want to forget what they've learned.
I am looking for the following features:
- good responsiveness (no noticeable lag between touching the keys and hearing the notes)
- no ads
- ideally in the $1 - $10 price range (lower is better unless the program is particularly great, but I'm willing to pay for quality)
- doesn't take up too much memory (sorry, GarageBand -- 800MB is too much space to part with on a 16GB iPad)
- key size comes close to that of a real piano
- reasonable number of keys (perhaps a way to shift octaves if necessary to expand range)
- no crazy gimmicks (notes arranged like a piano, not in a spiral or pulsing different colors or other weirdness)
Can anyone recommend software that works well for a use case like this?