Experiment shows mobiles are harmful? (Not the popcorn one)

So here's a good experiment you could try, he shows that it cant be magnets doing this, is this a trick or real?

He gets one phone to ring another, and in the middle of them under a glass places whats looks like something silver, balanced on top of a pin, with the pin pushed into something at the bottom to keep it in place, you will see what i mean by watching the video.

Is this a trick, if real is it harmful to us?

Video

I'm not sure if I did it correctly since he didn't really give precise plans for the experiment but I got nothing.

Use of an air jet is possible even though everything is supposed to be "visible". Note that the table itself is opaque rather than being a plexiglass sheet or glass. It could be concealing a small hose and a hole to blow lightly on the foil. The foil on a pin tip hardly takes any torque to spin.