Spotify has hit 15 million active users just on the strength of its iOS apps, and now that Android users can listen for free that number is going to shoot up.

The subscription music service announced today its Android app was finally getting the one feature that accounted for 11 million Spotify users: free music. The app has been updated with a new listening option that removes the need to pay for the subscription. You’ll have to deal with ads, but that is the cost of a free service, of course.

TechCrunch has more details:

As for why the long-awaited feature is only now making its way to Android, product manager Donovan Sung noted that it was an issue of balancing priorities. According to him, one of the reasons Radio for Android spent an extra month in the oven was because the team was “focused on making the Android app a lot better” first.

Spotify is now up to over 15 million active users, with over 4 million  of them paying for a subscription, according to Ken Parks, Spotify’s chief content officer. That’s a significant increase since last September, when they reported having 2 million subscribers.

You can find the app in Google Play.