Search:

It will be free if you already have a current Sirius and/or XM sub after the initial cost of the app....

What do you mean? As in "paid" do you mean a monthly payment above your monthly subscription? There is a Windows Mobile app called SelectRadio that you pay for once, but it's free to use after that...

What is Sirius/XM's current arrangement with these companies that have apps already?

http://www.selectradio.com/index.html

http://www.siriusmac.com/SiriusMac.html
...