Helio Workstation - Cross-platform lightweight speed-painting tool for creating music.
RapidComposer - MusicDevelopments RapidComposer: Music Prototyping and Automated Composition Software
Sibelius - Sibelius is a virtual score creation tool which allows composers to easily create new piano scores, developed by Avid.
Captain Chords - Write chord progressions in your favorite DAW
Guitar Pro 7 - Create, play and share your tabs
Odesi - ODESI is a music sketchpad that exports your projects to Audio and MIDI.