PlaYo

You might think that PlaYo is illegal, but that’s not the case. The application makes of the SoundCloud API, which is built by SoundCloud. This means that the PlaYo application only acts as a very clever interface to the SoundCloud music streaming service, which is completely legal.
 
There are no ad breaks and no limitations with PlaYo. Users get instant access to millions of songs and artists, they can organize the content in playlists, they can listen to the freely available online radios, and the application will continue to function even if you close the screen.
 
PlaYo is a completely free application, and it will remain like that for the foreseeable future.