Q. Why can't I see the other person I am talking to as the larger screen? A. This happened when chatting to my mother in lock-down 350 miles away. I believe it is because one of us inadvertantly switched on "screen sharing". This effectively shows the other person what you are seeing. So if I switch it on accidentally my mother sees my laptop screen on her ipad. She sees herself fullscreen and me up in a corner because that is what is on my screen. Nothing she does will correct that. I need to switch off my screen-sharing to give her back her normal video feed from my webcam.