Duplication cheat in Minecraft: Pocket Edition

Go to a chest and put an item you want to duplicate in it. Once you put it in, exit out of the chest. Wait 5 seconds, reopen the chest and take the item out. Really fast, exit out of the chest and then exit out of the whole app from the home screen. Reopen the app and select the world you were in….. The item you duplicated should be in the chest. Enjoy!!!!