Sibelius - Sibelius is a virtual score creation tool which allows composers to easily create new piano scores, developed by Avid.
Day One - A simple journal application for the Mac, iPhone, and iPad. AboutTo learn more about Day One, see these two excellent reviews . PublishPublish is not available in Day One 2.
MMA - “MMA—Musical MIDI Accompaniment” is an accompaniment generator.
Journaly - The customisable journal app
Sundog Scale Studio - The MIDI chords and melodies laboratory
Journalistic - A simple, yet powerful micro journaling app