For all the talk that in the not so distant future, your mobile device - if it isn't already - will control your in car entertainment, has anyone come up with an aftermarket stereo that does just this?

The reason I ask is I'm in the market for an old, beater pickup to use on weekends and possibly plow the driveway. Depending on how often I use is for for how long each time, I'd like to have some music to listen to. What I don't want to do however is install even a cheap stereo system with a head unit that I will likely have to hack into the dash. All I want so something super stealthy that will work with my phone through Bluetooth or a cable interface. No display needed, or volume control for that matter. Everything would be controlled through my device.

Does such a thing yet exist?