Is it possible to know if an iPhone is paired with the hands free system in a car using the CoreBluetooth or the EAAccessoryManager? If not, is there another way to do it?
If the iPhone considers the car an accessory you can get the connected accessories by calling:
[[EAAccessoryManager sharedAccessoryManager] connectedAccessories];
This will return an array of EAAccessory
objects which you can then query to get certain information like the name: accessory.name
.
I don't know for certain of this will work with cars having never tried it myself (I have used it with other accessories), so I would suggest that you create a test app that logs the connected accessories to the screen on demand and test it yourself.
Here's the documentation for EAAccessoryManager and EAAccessory.