Told what to play.
Play it. It confirms. Move on.

This is the real practice loop that will run on your phone — here on a synthetic fretboard, replaying recorded engine runs. Press play, or type a request like “show me C major triads” and watch the target light up, confirm note by note, and hand you the next one. On the phone the same overlay draws onto your real strings; that live camera tracking is still in development.