Well after having both a 3G and a 3GS with neither working in my Terrian i got an Iphone 4 yesterday. On my way to work this morning not expecting much i plugged it into my Terrian thru the USB.......... OMFG it works!!!!!! The steering wheel controls work with it as well!. I was really surprised. Not only that it will play music while you do other stuff on the phone check e-mail ect. Not that you should be doing that while driving.