Gnoosic - Even if you don't know what you are looking for - gnod will find it.
22tracks - DJ curated Spotify playlists on iOS
Musicroamer - A visual Pandora for discovering new music
tradiio - Reward-based music discovery app
LivePlasma - Discovery engine map for books, music, and movies
Noon Pacific - The week’s best music handpicked & delivered to your devices