When Cat is talking about the report they're doing, on Tori's computer screen, Cat has her clip in her hair. When the camera pans on Cat in her room her clip is gone. Then, when it returns to Tori's screen, her clip is back on.
Tori video-chatting on a plane should have caused noise which would have disturbed other passengers. Yet the stewardess never intervened.
Before the captain turns off the seat belt sign, passengers are already roaming the plane.
It is shown that Tori and the others cannot see their own webcam display box in the chat, and yet Andre, Cat and Beck somehow knew what the effects looked like and commented on them.
After André's grandmother cracks his screen, you can see the screen crack show up on Tori and Beck's computers. However, unless she actually cracked the webcam lens, they wouldn't be able to see his screen cracked as the webcam would still show André himself.
After Beck starts spinning his video chat window, Cat asks, What effect is that? He replies, Spin clockwise. Neither bit of dialog is in sync with their mouth movements.
Cat starts crying when Tori barely yells at her to stop acting like a child but in the later episodes. Jade can be seen and heard yelling at Cat at the top of her lungs but Cat doesn't cry.
Tori does not know who MrSkinnyJeans on chat is, but he is already in her friends list.