the app works as follows, depending on how you turn the phone it acted differently.
first for the magic start speak for the person to draw a geometry figure between circle, square, triangle and star, and after drawing write a number from 1 to 5 inside the figure. leave the phone facing down with the screen. now tell him to show it to all people and even you.
attention
if you untap the phone from right to left the figure will be a square
from left to right a triangle
from top to bottom a star
from bottom to top a circle
train before doing magic
After this part tells the audience more about magic, in the meantime, throw the screen of the cell to the left, and the time in seconds that you hold the screen in this way will be the number in the middle of the figure that the person chose. finally press reveal.
in the images below will show how to open the tutorial menu, and how to activate a beep so you know in which number is the time to hold the cell phone tilted.