There are plenty of great music apps for the iPhone, but Pandora excels at giving you something to listen to when you’re not exactly sure what you want to listen to. Simply specify an artist you already like, and Pandora will deliver a stream of songs by that artist along with songs by similar artists.
The app is free and ad-supported, though you can remove the ads for $4 per month. Pandora’s website mirrors the app — and vice versa — so all of your personalized radio stations stay with you wherever you go.
Link: Pandora Radio