For whatever it's worth, this is the setup that I have in my car. For reference I have the REC head unit with the 6 disk changer, with satellite radio (activated) and navigation. With these the two items I have listed I can still operate my Sirius radio and navigation while I have my iPad mounted in a cradle located in front of my dash vents and out of line of view. It's also really nice because if you have your iDevice hooked up you can change the songs with your steering wheel controls. You don't have to take your eyes off the road. But I also have the 3.5mm AUX jack so I can use my Android device to play music, however I still have to use my Android to skip songs etc...
iDevice wiring harness; http://www.autotoys.com/x/product.php?productid=12317
3.5mm Aux jack; http://www.autotoys.com/x/product.php?productid=11686
To hookup the aux jack you just plug it in to the RCAs that come off the back of the iDevice wiring harness and it feeds the music through your stock stereo with honestly what I would call cd quality sound. It works 100 times better than a FM modulator or anything of that nature.
Best Regards, Nick Schultz
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