Fretronome

Fretronome is designed for guitarists to support them in learning the notes and intervals on a guitar fretboard.

It's pretty simple, with the first button press it selects a note or interval on the fretboard, with the second it displays the name of the note or interval.

It also contains a basic quiz mode where you can test your skills

Support for left-handed guitarists (Fretronome settings in the iOS settings app)