Tonelib JAM - Create, edit, print and listen to tablature and guitar sheet music
Tabler - Admin panel made simple
Aria Maestosa - Aria Maestosa is an open-source (GPL) midi tracker/editor.
Jet Admin - Build business apps really fast
Chordsheet Maker - Create chord sheets or lead sheets quick and easily from your iPad. Add rhythms, endings, segno, codas and all what's necessary for your musicians to know what's your music about. Transcription made easy!
Forest Admin - Execute fast and at scale with no time wasted on internal tools developed in-house.