I am currently working on one myself. Apple will only let you sign up for the made for iphone program if you are a company. There Are several things that need to be done to get signals into the iphone. One involves a proprietary application serial protocol where the iphone is told that it is supposed to input from the 30-pin connector's R and L stereo input. Getting signals out is easier, and is accomplished by putting a resistor across two pins on the dock connector.