As of February 15, Last.fm fans will no longer be able to use the service's free radio feature on mobile apps and home entertainment devices.

It will remain a free service on the Last.fm desktop app. And according to a blog post on the Last.fm website, the radio service will also stay free on the site in the U.S., UK and Germany, and for those in the U.S. and UK who access it via Xbox Live and Windows Mobile 7 phones–but when it comes to other mobile apps and electronics like Sonos, Last.fm users will have to start paying  for the ad-free radio experience.  

"On the Last.fm website, an ad-supported, free-to-listeners model is what supports our online radio services in the US, UK and Germany," the blog post explains. "In other markets and on emerging mobile and home entertainment devices, it is not practical for us to deliver an ad supported radio experience."

Last.fm is now the same as other music subscription services like Pandora (News - Alert) and Slacker Radio. Slacker costs about $47.88 for its premium service, while Pandora costs $36 for a one-year subscription. A subscription to Last.fm costs $36 per year as well.  Pandora and Slacker, however, still have free, ad-supported apps for mobile.