Spotify - Map shows when two people play same song at same time
Noiseblend - One-tap music for every occasion, with Spotify Premium
SoundCloud - Enjoy music & follow favourite artists
22tracks - DJ curated Spotify playlists on iOS
Last.fm - The world's largest online music service. Listen online, find out more about your favourite artists, and get music recommendations, only at Last.fm
Pandora - Pandora Radio is a free (ad-supported) internet radio founded in 2000.