This has potential, but staring at red screens hurts my eyes. If you enlarged the grid to be able to clearly see and input intervals (probably not that hard on

This has potential, but staring at red screens hurts my eyes. If you enlarged the grid to be able to clearly see and input intervals (probably not that hard on iPad), you might have a actuated instrument interface a la Wang, Overholt, or Berdahl. http://actuatedinstruments.com/ http://actuatedinstruments.com/ I read music well on piano, clarinet and flute, but very poorly on guitar, FWIW).