The app forgets its in-app purchases randomly and I have to Restore them pretty much on every fresh launch. I have in-app purchases disabled, so its a hassle - I have to enable them in Settings, restore in the app, disable them back in Settings. This is an-no-ying.
Secondly, until purchases are restored the app uses heavily distorted piano sound, making itself completely unusable. Must be some sort of anti-piracy thing, but having paid several $ I dont expect finding myself on the receiving end of it.
Thirdly, at $2 per pack the app is just plain to expensive for a toy that it is.
Duhshu about Touch Pianist - Tap in Rhythm and Perform Your Favourite Music, v1.0