Looking for a way to win back some market share lost to mobile music applications, flagging new car sales and the loss of Circuit City and a distribution partner, Sirius XM Radio is making the leap onto the iPhone.

In a move meant to both give current subscribers broader access to their favorite satellite radio stations and grow its customer base, Sirius plans to launch an iPhone app in Q2, mocoNews reports.

No word yet on what type of subscription will be required to use the application, but we hope it's less than the $13 a month non-subscribers have to pay to listen to Sirius over the Internet.