Simple Android / iPhone Camera Trigger using Audio Jack

Hey guys,

I am currently looking for a way to trigger the iphone / android stock camera through audio jack ...

Am planning to trigger the camera from arduino ...

iPhone triggers the camera if the volume buttons are pressed and android triggers the camera if the play . pause button is pressed in the wired headset..

It will be great if you can point some references to any circuit to trigger the iPhone / android camera...

I found this

http://david.carne.ca/shuffle_hax/shuffle_remote.html

HTH

[ UPDATE ] Not working man...

I tried this circuit and a few other available in the internet... got it working for the android using the TRRS plug system... but its not working for iPhone

Is there any other simple way to trigger the stock camera in iPhone...

Will be very helpful if any one can post any leads...