I installed iOS7 on my iphone and now when I connect my phone to my '12 accord ex-l w/o nav I get an "unsupported" message on the display. I think this is an Apple issue. I have been googling it but have not found a solution. Anyone else experiencing this?

 

Is the message on the phone? or on the head unit display?
I have seen that message a couple of times on the phone, and I think it has to do with when the cable is plugged in and the power port not energized. I think it is similar to the message with the power adaptor doesn't deliver enough voltage or amperage to charge the phone.
Mine works fine with the radio. But I am finding that I am using the BT more than the cord lately.

 

The Honda OEM head unit displays the error. I would like to use BT, but its unsupported by the honda radio in the car.

 

sounds like either Honda needs to upgrade the radio's firmware (not likely), or you will need to wait for an update to iOS7 to fix the backwards compatibility.