Apple boasts that the 3D Touch Display from the iPhone 6s and iPhone 6s Plus added a new dimension to the handsets due to its functions. Some of them are pretty useful, such as previewing emails without opening them, shooting dynamic pictures or locating an address instantly.

Weighing plums, however, is a less known but essential capability of the 3D Touch. A developer in Paris coded this app, having in mind the interest of fruit shoppers and vendors.

Simon Gladman described his app in a blog post, using a casual tone. He says that Plum-O-Meter uses the advanced technology in the pressure-sensitive screen to act as a scale: the app signals which of the objects placed on the display is heavier.

Gladman knows that a picture is worth a thousand words, so he made a video to showcase his developer skills. He takes three plums and placed two of them, simultaneously on the iPhone 6s' display. The app measures the weight of the fruits and creates a yellow circle under the heavier one to signal the winner. It also shows a percentage comparison between the plums.

Plum-O-Meter is open source and curious users may sideload it on both iPhone 6s and iPhone 6s Plus without jailbreaking. According to reports, the capacitive screen on the Apple flagship is able to discern five different objects that are placed on it.

"I did originally build this app for grapes, but they're too light to activate the 3D Touch," Gladman details in his blog post.

If you plan on weighing apples, lemons or coconuts on the iPhone 6s or 6s Plus screen, it might be wise to thoroughly clean the display beforehand. Or you can just make sure the fruits are clean before placing them on the pseudo-counter.

An interesting note is that Apple is hardly the only smartphone where fruit-weighing is possible thanks to a pressure-responsive screen. Huawei described its Huawei Mate S' Force Touch in a press event, and it presents similar features with the 3D Touch. Comparing the two displays, Apple's 3D Touch seems to have hit the sweet spot, while Huawei's prototype still needs a bit of tweaking.