News Summary: Spotify offers free mobile radio

THE OFFERING: The music-subscription company Spotify is offering a free radio service for mobile devices in the U.S. Until now, the company charged people $10 per month to use its mobile app.

THE COMPETITION: Spotify joins Pandora, Slacker and Songza in doing so.

THE BENEFIT: The free service, which comes with audio ads, is a way for Spotify to entice people to sign up for a paid subscription, which strips out the ads and enables users to choose songs.