My conclusion from looking at the game in the image: that is likely to not be a real game.
From where the store clerk is tapping, it doesn’t look like he has any goal in particular that he is trying to do with the game. I don’t see any buttons or avatar either that he could be tapping or controlling.
My guess would be that this “game” is a placebo or something to make it seem the clerk is playing a game or being busy on his phone.
Hope this helped! Should I get any tips I will update my response.