Not Worth It
Saw OnlinePianists great, high quality YouTube videos and it suggested the app, which I downloaded only to find out that you have to pay a crazy amount for an app that is barely functional. If you could fix the quality of your app I might be willing to pay the premium, but with the current quality--no way.
SirWilliamWallace about
OnlinePianist:Play Piano Songs, v1.5