JamBuddy - Find and collaborate with musicians around you thru Spotify
Symphona App - Designed to make orchestral staff management a breeze.
TigerGraph DB - Application and Data, Data Stores, and Graph Database as a Service
Undrtone - Social layer on top of Spotify and Rdio from Scott Vener
Jammcard - The private network for music professionals
Stereofox - Find awesome new music, explore artists & create playlists