Suffering from the dearth of new-car buyers to sign up for its service, Sirius XM is expanding with a new application to provide satellite radio over iPhones and iPod Touch devices.

Rather than a satellite feed, the service would stream satellite radio content over their built-in Internet connections from Sirius XM’s Web sites.

Several other streaming radio applications are available for the iPhone and iPod Touch. Most provide free content. But the Sirius XM feed would presumably require the company’s usual $13-a-month subscription, just as listening to the services online does now. The news came in a conference call on Sirius XM’s earnings this week, but there was no word on when the service would be available. (The iPhone in this blog just illustrates the concept.)

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—Eric Evarts