The popular and formerly free radio app is about to become a premium, subscription-based service for mobile users. On February 15, the radio service built into mobile apps and on home entertainment devices will become an ad-free, subscriber-only feature available at $3/month. on the desktop will continue to offer ad-supported radio listening for free in the U.S., U.K., and Germany. Users in the U.S. and U.K. will also be able to listen for free on Xbox Live and via the Windows Phone 7 app.

Long-term users and early adopters received an email from earlier today about the news. The email offered appreciated for “what you have meant to our growth and success,” and a free 3 month subscription to as thanks. All other users on mobile devices will have to subscribe immediately to continue listening.

On their blog, Last.Fm explains that “You’ll see that this change brings us in line with other music services that already charge you to listen to music on mobile devices.” These other services, such as Pandora, Rhapsody and Rdio, do use a subscription model, but cost comparatively less. Pandora is offered for free, and the other services, though with a slightly higher monthly price tag, offer music on demand and even the ability to legally download songs. These types of options are not available on Last.Fm.

Thankfully, Last.Fm notes on their blog that the new subscription model “only affects the radio component of’s services on mobile and home entertainment devices.” The social and sharing functions of Last.Fm, such as scrobbling, music and event recommendations,  and’s wiki-based artist information pages will remain free and unchanged.

Would you pay $3/month for Last.Fm as a premium subscription-based service? Would you even pay for a music service like Last.Fm?