This is very nice. One suggestion based on a guitar related hobby webapp I built myself: fretboard renders in potrait probably makes for nicer ux.

My tool does not focus on strumming at all as this one does though.

Nice work. Am having fun with it.

Thank you! Yes, I tried that, but since the app focuses on strumming, I couldn't use all the space for a long fretboard. I'm still working on a better mobile UI.