Touch the screen and ask to open the door - loud knock on wood simulate the arrival of guests. You forgot to close the lock?
Tired of sitting at the banquet table and tired of boring family? Choose one of the four doors and touch screen. When you hear a knock, tell parents that you open and run out to play!
Do you want to play with cat, but are afraid to scary him? Touch the screen and a loud knock on wood may attract his attention.
You do not know how to entertain themselves in the classroom? Hide the phone under the desk and quietly turn on the app - if you're lucky, the teacher thinks that the door someone knocks, and will go to open it.
WARNING: app Knock on door - prank. Do not beat around the screen too hard - the sound of it will be no louder, but the phone can break down. Do not forget to lock the door of the castle.