Apple MacBook Pro and MacBook Air: Touchpad becomes a scale thanks to free app

The Apple MacBook Pro and the MacBook Air have a haptic trackpad that not only detects whether a click is being made, but also how hard the click is applied. Apple uses this function for gestures, for example, allowing users to look up individual words with a firm click. Canadian developer Krish Shah has now succeeded in converting the trackpad into a small scale by evaluating the collected data and thus calculating the pressure and thus the weight of the object on the touchpad.

The result is an app called TrackWeight, which can be downloaded for free from GitHub. This app allows users to weigh objects that are not too heavy, but with a number of limitations. Firstly, the trackpad must be touched with the finger while an object is being weighed. Secondly, the weighed objects must be small enough to fit entirely on the trackpad. Thirdly, electrically conductive objects can only be weighed if electrical contact is prevented, for example, by a piece of fabric.

Also somewhat cumbersome is that the TrackWeight source code must be downloaded, compiled and run in Xcode after disabling the app sandbox in the project settings. According to Krish Shah, TrackWeight can measure the weight of objects relatively accurately, but the developer emphasizes that the app is currently still experimental and the results should only be considered a guideline. Objects that are too heavy can cause damage to the trackpad; the app has been tested up to a maximum weight of 3.5 kilograms.