Try to figure out to whom the mystery face the mobile has chosen belongs to. For that, you can ask a series of questions focused on the physical description of all candidates in order to progressively eliminate those that do not fit.
When a question gets answered the faces that do not fit the description are automatically removed from the game.
When you are fairly sure of whom the mystery face is you can press the “Guess” button and type its name but beware, you only get one chance and you will lose the game if you are wrong!