If you're an iPhone owner who opted to go the way of Amazon's storage locker as a means of streaming music, then you know listening to music on the go hasn't exactly been convenient (unless you actually like navigating Amazon's site in Safari). But Amazon finally got their act together and released a proper music app for the iPhone.
Amazon Cloud Player gives you a touch friendly interface, allowing you a much easier path to your music. You can switch between playlist, album, artist, song and genre views, as well as toggling between music that's stored in the cloud and locally on your phone. Granted, you still have to buy all the music that you listen to, but it's generally cheaper than iTunes and doesn't require a monthly fee. [iTunes]