Festify - Festify is a free Spotify-powered app that lets your guests choose which music should be played...
Playlist Machinery - Tools that help you create & organize your Spotify playlists
Twinjack - Stream Spotify music with anyone with just a link
TrackStack - Easy Spotify playlist sharing and collaboration
Parallel - Listen to music with friends over Spotify at the same time
BeatMix - Enables Shuffle and Radio for multiple artists in Spotify