One of the best features I've found on the iphone is the ability to switch between different audio sources. For example I can be paired with my BT earpiece, get in my BMW and switch to my car's BT seamlessly, switch to speakerphone if wanted, switch back to my earpiece BT when I leave my car again, and all without interrupting the same phone call. This is something that has stymied me with every other phone I've had. I would always be stuck when I was on the phone in my car and got to my home, because if I tried to disconnect from my car BT and go back to the phone speaker I would invariably get cut off. I just finished a 90 minute conference call where I alternated between speakerphone, BT earpiece, and BT car, all with no problems transferring. Wonderful.