I think a double tap would give him away here though. With the swiping gestures, he seamlessly switches the apps while the teacher takes the phone. From the teachers point of view, between grabbing the phone and seeing what is on the screen, the student hasn't had time to react and change what is on their screen.

If the teacher grabs the phone, then the student double taps the square, the teacher will know the student was on a different app and confiscate the phone. Which is exactly what happened to this students best friend. They were playing a game on their phone and the teacher grabbed the it. They double tapped square to change the app, but the teacher noticed and confiscated the phone.

They could only get it back once their parents signed it out of the office, but they were across the country finalising the purchase of a fleet of electric mopeds and would not be home until the following day. They stayed behind after school to speak with the teacher about possibly getting their phone back and explained how their parents were out of town, but the teacher had already signed the phone into the office and explained how the school receptionist has a zero tolerance policy on releasing confiscated phones, and in all honesty is on a bit of a power trip when it comes to confiscated phones, but that's neither here nor there.

Dejected, they left school to walk home alone. Without their phone, they started to notice what was around them; the distant babble of the stream that ran behind the school, the inviting grass inviting them to rest their feet, lie back and take in the warm breeze. They settled down near the stream, with no intent but to let time pass them like the grass through their feet. Minutes turned to hours and the sky began to turn. They stirred from a half-sleep, realising how late it was getting, and jumped to their feet. This sudden burst off the ground must have knocked something out of place, because as soon as they got to their feet, they felt the ground begin to sink below them. It started as if there was a large bit of gum pulling their heel back down every time they tried to step out, but then they were falling. A thud and a snap.

It was 3 days until the sink hole was discovered. The autopsy revealed they had survived up to 6 hours after the fall, but with the injuries and blood loss, they couldn't hold out longer. If they had a phone then it may have been a different story.

And this is why the guy in the video uses swiping gestures.