YT Music - An unofficial Mac app for YouTube Music
Youtube Detox - Distraction-free Youtube search
Deezer iMessage app - Share your music on iMessage with Deezer!
Radios.YT - Listen to the best YouTube music livestreams for free, 24/7
SoundCloud Desktop - Use your media-keys ⏮⏯⏭ with SoundCloud
CandyLists - Create interest based YouTube feeds