Weird name I know but if you want to keep your OEM or older aftermarket stereo and want Bluetooth, hands free cell phone all in a tiny package then this thing is for you. It looks like a simple two outlet USB charger. Not only does it charge but it also does everything I mentioned above and more - http://www.roidmi.com/en/lcindex
It's around $40 on Amazon and has both Apple and Android Apps. The iPhone app got terrible reviews but I had no issues. Registration was a little clunky but once that was done I had my phone paired and programmed in a clear station with in a few minutes.
Finally a CRX only tip when using it - don't shove it all the way in, just place it in the cigarette lighter then use just a tiny a bit of pressure to keep it from falling out. If the light's on it's working, too far in and it won't.