EarMaster - Professional software for ear training and practical music theory on Windows and Mac.
AIVA - The AI composing emotional soundtrack music
Meludia - Listening exercises and to sharpen your ear and music theory skills
Abundant Music - Generate royalty free music with a simple but very powerful procedural music creator
GNU Solfege - GNU Solfege is free music education software.
WaveBots Editor - Procedural music and sound maker that exports to Wav, MIDI, GoatTracker and much more.