free app to learn intervals on guitar neck

This is a free app to learn intervals on a guitar neck. Click on the note to play it. It has intervals for standard and some drop tunings.

It has a right-handed and left-handed mode.

Intervals are the distances between any two notes. All harmonies or melodies can be considered as a sequence or layering of intervals. The quality of an interval can be Perfect, Diminished, Augmented, Major, or Minor.