The number of FM transmitters on the market for smartphones like the iPhone and Android devices is massive. If you use an Android phone and want a solution that will allow you to get the tracks from your phone onto the stereo system in your car with no wires TuneLink Auto for Android will do the deed come mid-January.
The device is a cool little DC adapter that fits almost all the way into your car DC power port. The adapter has Bluetooth tech integrated that syncs with your phone to wirelessly shoot tunes to the car audio system. The adapter also has a USB port on it for charging your Android device when needed.
A line in jack is integrated as well for playing music from devices that don't support Bluetooth. The device will allow the pairing of more than one Bluetooth device at once. The FM transmitter portion of the device is controlled by a free app on the Android Market. The system will sell for $99.99 when it lands next month.