No no, I mean he's talking into the top of the phone, perhaps where the loudspeaker microphone might happen to be, totally depends on the model of phone/tablet though.

They got multiple microphones these days, not just the one at the bottom of the phone. Put it in loudspeaker mode and it uses a different microphone away from the bottom speaker.

Any which way, if you turn the phone upside down in portrait orientation, the screen won't flip 180⁰, because 'smart' phones are too stupid to do that.

Edit: My comment is in jest, but at the same time I have to talk into the left side of my tablet, because thats where the main microphone is.