Arduino Uno / iPhone / OSC, Beginner Question

I would like to do a project using a Arduino in a car controlled by a iPhone, really just switching relays for the moment.
Googling around I've seen what's possible with OSC, Blackwidow, WiFly and ethernet shields, but all run over a host Mac/PC running Processing.

So can anyone tell me if it's possible to get it running without the need of a "middle man" Mac/PC

Thanks

Regards
Ian

Bluetooth arduino? If you knew how to code it it would probably be ok, but I'm not sure how to do that.

You want send information/sensors/command to arduino from i Phone or opposite?

If you wanted, you could get an Xbee, hook up the iPhone USB to an arduino, write some code on the iPhone to send stuff over serial. then send that from one arduino to another with the Xbee. A bit complex, and you'd need to know a lot to do it.