Spotify is a commercial music streaming service providing digital rights management-restricted content from record labels including Sony, EMI, Warner Music Group and Universal. Music can be browsed by artist, album, genre, playlist, or record label, as well as by direct searches. On computers, a link allows the listener to purchase selected material via partner retailers. Spotify music streaming is available on all Android and iOS devices and on desktop computers for unlimited durations. Features like offline listening and ad-free playback are only available for Premium subscribers of the service.