Apple Music - Apple Music app combines your personal iTunes library with Apple's music subscription service. Music you have purchased from the iTunes store, or synced over from other sources, is available in the "Library" tab. Read more about Apple Music.
Playlist Machinery - Tools that help you create & organize your Spotify playlists
ThinMusic - ThinMusic is a free web player for Apple Music with support for last.fm scrobbling.
Pandora - Pandora Radio is a free (ad-supported) internet radio founded in 2000.
Musish - A web client for Apple Music
22tracks - DJ curated Spotify playlists on iOS