Openwhyd - Collect and Share the tracks you love.
MusicTwin Finder - Find your MusicTwin by your Spotify playlists in 5 seconds.
Zoff - Collaborate on a live music and video playlist with your friends.
Symphona App - Designed to make orchestral staff management a breeze.
SoundClick - SoundClick is a music-based social community.
JamBuddy - Find and collaborate with musicians around you thru Spotify