With the use of Bluetooth technology, HTC was able to come out with the CAR A100 StereoClip (AUX) for your HTC smartphones. The AUX stands for auxiliary input. 3.5mm input just like you would find for headphones.
The HTC StereoClip has been getting a lot of publicity for a reason. It is a simple piece of technology that adds Bluetooth abilities to your car when they were not there to begin with. That is a huge feature.