This app started as a project at my university. Back then, I had tried several music production apps on android and I was kinda disappointed by all of them using piano-like keyboards. As an amateur musician, and knowing some bits of piano playing, I just don't see them practical on a touchscreen because you don't get the same feeling from the keys. I mean, there's no real physical separation between the keys, and you cannot have the sensation of pushing on a key... So then, why don't you let your fingers slide on the screen instead of lifing them and pressing again to play a new note ?