On the same day Spotify rolled out mobile radio for Android devices, the music-streaming giant has now announced some interesting new figures.

At today’s Global Business Summit on Creative Content in London, Spotify’s Chief Content Officer and Managing Director of Spotify North America, Ken Parks, announced that Spotify has over 15m active users, with 4m paying subscribers.

It would be interesting to see a breakdown of these figures from around the world, but it’s probably fair to say that Spotify’s launch in the US last summer has had a significant part to play in this recent growth spurt. And it also represents a growth of 1m paying subscribers since January, when the company reported 3m paying members – though curiously, this was said to constitute one fifth of its active users, which means it would’ve had 15m active users then too.

It’s hard to believe that it hasn’t brought on board completely new members in that timeframe, so it could be that its definition of ‘active users’ has changed, or a roughly-equal number of people have left the service, as to those that have signed up. We have reached out for clarification from Spotify, and will update here when we find out.

Update: It seems the official announcement earlier this year cited 3m paying subscribers and “over 10m active users”, so the original reports suggesting 15m users weren’t necessarily accurate. Spotify is now officially claiming 15m users.