Last.fm has decided to tweak its offering on the app front, where it is now introducing a new subscription requirement for most mobile and home entertainment devices. From here on out, you'll have to pay for the privilege of streaming music through the company's software on devices like the iPhone and Squeezebox, though the blow is nicely cushioned by the news that there won't be any ads to dilute your aural pleasure. Windows Phone 7 won't be subject to the new fee for the remainder of 2011 in the US and UK, while Sonos devices will continue to stream freely until this summer, but eventually it seems like all these apps will cost a little bit of cash to use. And "little" is the operati