I have a usb connection and an aux-in. If you connect your iphone to the aux-in and to usb using separate cables you car wont play anything and an error saying your using the wrong cable will appear. You have to get the OEM y cable. I got one from amazon that works great and charges my iphone, which the oem cable doesnt do (thats what ive heard). http://www.amazon.com/gp/product/B00...00_i01_details
Dont get the really cheap one though!
You may want to get an extension cable because this cable is really short and you wont be able to take your iphone out of the center console.