It is a split application using AR, which you can use when dividing cakes and pizzas.
When recognizing the space, the target will be displayed on the screen, so you can put a guide with the "+" button. You can adjust position, angle and size by drag, rotation and pinch gestures.
Since it corresponds also to a rectangle besides a circle, please use here when dividing a roll cake. The division corresponds to 1 to 12.