Subscribers will be able to download software allowing them to listen to Sirius XM on an iPhone or iPod Touch (using WiFi) without an additional fee, for those who subscribe to the Internet option. Others will pay $2.99 per month for premium online service. Reuters reports the venture will allow Sirius XM “to gain and retain subscribers, by providing easier access to its news, talk, music and sports programming through means other than its traditional satellite-based platform.” Sirius XM recently announced that it had lost about 400,000 subscribers between the two most recent quarters, and blamed that on sluggish car sales.