Apple CEO Tim Cook made an appearance at a conference this week and revealed that Apple Music has 6.5 million paid users.

The music subscription streaming service that launched back in June following an earlier announcement at Apple’s Worldwide Developers Conference (WWDC) also has 8.5 million additional users on its three-month free trial.

During Cook’s appearance at the Wall Street Journal’s WSJ.D Live conference, he noted that human curation was the key selling point for Apple Music over rivals like Spotify or Pandora. However, considering the presence on playlists on the majority of other services, it’s unclear how this differentiates the service. Of course, Apple Music does have its 24-hour ‘Global’ radio station.

Read: Our three-month review of Apple Music

To put Apple’s subscription numbers in context, Spotify recently hit 20 million paid users after seven years in the game, while its overall userbase including its free tier is over 75 million (Apple Music doesn’t have a free tier).

Back in August it was believed that 11 million Apple customers had signed up to the service.

Its retention of 6.5 million users (while the remaining number could have started their trials later and may still stick around after the trial) are solid numbers for the new service.

They’re also like to grow considerably as the Music ecosystem widens with the launch of the new Apple TV box, which Cook was keen to promote. He revealed that the box would be available for pre-order from 26 October for shipping at the end of the week.

Apple Music costs $9.99 (£9.99) per month after a three-month free trial. Users can subscribe via the iOS’ Music app, or via iTunes.