Simply Piano - Fast and fun way to learn piano
Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.
Melodics - Melodics is a desktop app that teaches you to play MIDI keyboards, pad controllers, and drums.
Sketch - Professional digital design for Mac.
Yousician - Learn to play music at home, at your own pace
Affinity Designer - Professional creative software, exclusively for Mac.