Abundant Music - Generate royalty free music with a simple but very powerful procedural music creator
Sibelius - Sibelius is a virtual score creation tool which allows composers to easily create new piano scores, developed by Avid.
AIVA - The AI composing emotional soundtrack music
NtEd - Music Score Notation editor.
WolframTones - Listen to what I just found in the WolframTones music universe
Guitar Pro 7 - Create, play and share your tabs