I'm definitely not the target market for this, but I do want to say that this really scratches an itch for something that should exist, and I really want to compliment you on how fantastic the execution is! Very clean look in both the physical and digital realms, and I really appreciate just how fully featured it is! It really seems like the ideal version of what this product would be. Also love the idea of the bookmark pattern. Out of curiosity, is that customizable too?
+1 for this! Some considerations I thought of: 1. smaller keyboards don't easily have access to upper octaves. 2. User might frequently change the transpose on their keyboard.
Could there be a Create Bookmark Now button in the app as a fallback?