Rock On! - A song pop adventure - music trivia awesomeness
Magic Playlist - Get the playlist of your dreams based on a song
Songlio - Free musical guessing game: race friends to name that tune
Spotalike - Spotify playlist with similar songs, according to Last.fm
SongTrivia2.io - Songtrivia2.io is a browser and mobile blind test game that allows you to play in real time with your friends or against strangers. Several musical themes, difficulty and game modes are available to create lots of different musical quizzes.
Spotify - Map shows when two people play same song at same time