Cover your cellphone’s camera and place coins on top of it. What happens next is simply fantastic.

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Today’s smartphones can do so much more than simply receiving calls. Now an essential practical item for everyday life, few would dare to leave their house without their precious cellphone.
With a few adjustments, it’s now even possible to turn your smartphone into a mini set of scales. All you need is a suitable app, a post-it, and a resealable plastic bag («air cushion») to transform cellphones and tablets into scales.
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First, download the «Working Scale» app onto your Android device. Then fold a post-it so that the sticky sides are on the outside, and place it on the top of the cellphone or tablet. This will prevent objects you want to weigh from slipping off. Then place your device on the slightly inflated sealed bag.

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Open the app and wait until it’s ready to start weighing objects. Carefully place the object you want to weigh on the post-it (a coin, for example). The app will soon display the weight to the nearest microgram.
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You can see how it’s done with explanations by watching the following video:


There you go — a simple trick for finding out how much small and light objects weigh. Very practical!

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