Spotify announced free, on-demand streaming for mobile devices and that its adding Led Zeppelin to its collection. Spotify

Spotify, a popular music-streaming and Internet radio service, gives users on-demand access to its 20 million-song catalog for free with advertisements on desktop and laptop computer, but charges $10 each month for access on mobile devices. The Sweden-based company is now planning to release a free, ad-supported version of the service for mobile devices, according to the Wall Street Journal.

Spotify has been working on the service for more than a year, negotiating with the three major record companies (Sony Music Group, Universal Music Group and Warner Music Group), over the rates Spotify will pay to allow users free mobile access. Currently, nonsubscribing mobile users can only use an Internet radio service with advertisements.

The deal reached allows nonpaying members of Spotify to play a limited number of songs on-demand, but the songs available will be based on the user’s music preferences.

The record companies own a stake in Spotify, and the hope is that this new feature will drive more users to sign up as paid subscribers. Spotify has about 20 million active users, but only 6 million are paid subscribers. It will also provide a way for the labels to promote new releases to users, as well as make additional advertising revenue.

The details of the plan haven’t been officially announced, but it’s expected that Spotify will do so at a press announcement in New York next week.