This is cool! I made a similar app, but for guitar. However, I couldn't quite figure out how long I should sample. I wanted to make an app where it will play an interval and then you need to play it back on the guitar. If you can get this to work on a harmonica, I should be able to get it to work with a guitar. Will likely use your source for more inspiration, thanks!
Thanks! That sounds like a cool idea too. In Let’s Bend, I also included a scale training mode, where users can practice playing along with different scales. Maybe that could be useful for your project as well. Feel free to dig into the source code, and let me know if you have questions!