Full disclosure: I'm the dev. Let me know if you have any thoughts/suggestions :)
The app used to be a paid app that cost $20, but I decided to make it free for 45 days to open things up a bit. If you have an iPad and you like music, please try it out and play around.
Also, there's more detailed info about the app here (it was previously called Fiddlewax Pro). https://fiddlewax.com/pro/