Rhapsody just released a little teaser video for the next version of its iPhone app (to be followed closely by its new Android app) that marks a major change for the service: You can now download songs instead of streaming.

It's great news for users of Rhapsody's $15-per-month all-you-can-eat service, who can now simply download songs from the catalog for later use instead of depending on unreliable wireless signals. As the voice of Rhapsody's disembodied hand notes, that'll also save battery life, since just playing a music file is a pretty low-intensity function and streaming music is fairly draining on a battery. Even better, it'll reduce frustration with AT&T or a lack of nearby hotspots. The app is in the final approval process now, so it should be out within a few days.

Oh, and for Android users: The Rhapsody Android app, now in beta, is just about done with its testing time and should be appearing in the Android Market any day now. Rhapsody needs this kind of market coverage—if Microsoft's Windows Phone Series 7 phones are as good as they look, Rhapsody's going to be in a tough fight with MS's Zune Pass this fall. [Rhapsody]