Lunar.fyi - Control monitor brightness, adapt using the ambient light sensor, adjust volume, switch inputs and turn off displays without fiddling with clunky buttons.
Parallel - Listen to music with friends over Spotify at the same time
DisplayBuddy - Control the real brightness of your monitors directly from your Mac - no need to touch the buttons on your Monitor.
Slackbox - Spotify playlist collaboration through Slack
Nocturnal - Have more control over your screen at night 🌙
Join My Playlist - Listen to music live together with your friends in Spotify.