Download auto clicker from play store and then enter the app, then enable the multi clicker below the single clicker or whatever that thing is called, then you will see some kind of settings at the left side of your screen, then click the plus button and then you will see a circle with a number in it, and press it, change it to 1 millisecond and drag the thingy to the inventory box and enter the inventory and put things you want to duplicate to the box where you put the circle at and click play, before that press the button below the settings to make it invisible, then click play, then click the thing you want to duplicate and then click the button at the right down of your screen multiple times then voila you duplicate your things(sorry for my broken English)
