Magic Playlist - Get the playlist of your dreams based on a song
Parallel - Listen to music with friends over Spotify at the same time
Playlist Machinery - Tools that help you create & organize your Spotify playlists
Join My Playlist - Listen to music live together with your friends in Spotify.
Spotify.me - Beautiful analytics on your Spotify listening habits 🎧
TuneMeet - Chat with people who are listening to the same song