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There is an app for this. It is called "Camera" and it is preinstalled on your iPhone.

Simply place a facetime call and then grab another iPhone, point it at your facetime screen and use the camera feature to record it.
 
There is an app for this. It is called "Camera" and it is preinstalled on your iPhone.

Simply place a facetime call and then grab another iPhone, point it at your facetime screen and use the camera feature to record it.

This is an upgrade to the previous version where you placed a facetime call, grabbed a Camcorder, and pointed it at your facetime screen.
 
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