The app comes with a free 7-day trial but then costs $14.99/month if purchased through iTunes, or $9.99/month if purchased through Rdio's own website (reflecting a recent revision to iTunes' purchasing policy). Rdio debuted with an iPhone app last year, and also has web and desktop clients.
Rdio boasts a catalog of more than 10 million songs to choose and stream on-demand. Like MOG and Spotify, it's heavy on the social networking side. It lets you tap into the playlists of your friends on Facebook and Twitter, or other Rdio members, and post suggestions to their walls. It also highlights new releases and bestselling songs, and feeds recommendations based on what you've listened to before.
Malthe Sigurdsson, vice president of Product Design at Rdio, said an iPad version was its most requested feature to date. "Albums flip over to reveal track listings, transitions between portrait and landscape orientations are gorgeously animated, and controls and lists are cleverly laid out to show off album art in high definition," he said in a statement.
Slacker, a PCMag Editor's Choice award-winning streaming music service, and Pandora, also have iPad versions, but focus more on delivering songs and customized stations based on individual listening habits.
Rdio was launched last summer by Skype founder Niklas Zennström and Kazaa founder Janus Friis.
See how Rdio for the iPad works: