Apple CEO Tim Cook has revealed Apple Music – the company’s streaming music service – has more than 15 million users, including 6.5 million customers in the paid tier.

Apple Music went live on the 30th of June, so October is the first full month that Apple has started collecting payments from its first subscribers.

Talking at the WSJ.D Live conference in California, which was live-blogged by The Verge, Cook sat down with the editor-in-chief of The Wall Street Journal Gerad Baker to chat about Apple products, data privacy and social responsibility.

Speaking about Apple Music, Cook said: “I think it’s fabulous, and to have over 15 million on there, and 6.5 million in the paid category, I’m really happy about it. And I think the runway here is really good.

“It’s going really well,” Cook said “Fortunately, lots of people are liking it.”

Some commentators have pointed out that some of these 6.5 million people might not have intended to pay for Apple Music. Everyone signing onto the platform agrees to automatic subscription payment once the free trial ended.

Cook remained tight-lipped about the Apple Watch sales, he told the Baker “I don’t want to give anyone any information I don’t have to.”

Apple Music is now the second most popular music subscription service behind Spotify, which announced (just before Apple Music launched) that it has 20 million subscribers.