Free to download, the app will only work if users have a premium Spotify subscription costing £9.99 a month. Users are able to cache up to 3,333 tracks on their device for playback when they have no Wi-Fi or 3G connectivity.

There is no official confirmation on when the app will be available publicly except for Spotify telling Music Week that it will be coming "soon".

Much speculation has surrounded the app and Apple's approval procedure, especially in light of ...