Audio & sound design
Audacity https://www.audacityteam.org/
Freesound https://freesound.org/
Bfxr https://www.bfxr.net/
Game Art
Piskel https://www.piskelapp.com/
Gimp https://www.gimp.org/
OpenGameArt http://opengameart.org/
Game build software
Unity https://unity3d.com/
Scratch https://scratch.mit.edu/
Twine https://twinery.org/
Game story & narrative
Ink https://www.inklestudios.com/ink/
App development courses (online)
Apps For Good https://www.appsforgood.org/courses
Other
Games Glossary http://ygd.bafta.org/sites/default/files/uploads/ygd17glossary02.pdf
Accessible gaming wish-list https://www.specialeffect.org.uk/game-developers
