This whole project started as a result of being lazy and to reduce potential safety issues. In order to listen to my phone's music in my car, I had to directly connect my phone to an FM transmitter, and manage music playback from its touchscreen. While it worked, messing with wires and getting music playback going was a pain, and controlling playback was not exactly the safest. I could have used a fullscreen music player with giant buttons, but I use Waze for navigation and hazard monitoring. This left me with using a music control overlay which took up valuable screen area, and was not the easiest to use while driving.

An idea I had to solve this was to go wireless using bluetooth, and while the initial searches provided good results, they were too expensive. Eventually I ended up on ebay and this forum thread. The device in question is able to take a bluetooth music stream, and put it through a standard 3.5mm stereo adapter (compatible with my fm transmitter's input). With some simple hardware 'hacking', it is also capable of controlling music playback and more over serial using AT commands. A few hours ago, I purchased one of those devices.

Next on my list is to get some kind of power control system going, and then music control.