Earlier this year, British startup MusicQubed signed a deal with O2 to launch the O2 Tracks app, offering subscribers the entire Top 40 downloaded to their smartphones for £1 a week (Bulletin, 8-Mar-13). It’s been backed by a £7.3m advertising campaign from the mobile operator, so how’s it doing? MusicQubed has shared some stats with Music Ally, revealing that O2 Tracks has attracted more than 500k users and notched up 60m song plays since its launch, with users now averaging more than 55 minutes a day of listening. What’s more, 85k tracks have been sold through the app. As yesterday’s Sandbox report explained, a recent campaign on O2 Tracks for boy-band The Wanted saw their themed playlist being played 120k times in its first week. What’s not clear for now is how many of the 500k users are paying for the service: people signing up get two weeks for free, or eight weeks if they’re an O2 customer.