Without Wires or Bluetooth, This Case Lets You Add Buttons and Scroll Wheels to Your Smartphone

By Andrew Liszewski on at

It won’t be long before smartphones ditch every last physical button, but is that necessarily a good thing? Fewer components in a device means more profit for manufacturers, but users are left having to learn awkward touchscreen gestures to compensate. Researchers at Columbia University are bringing back the button with a customizable smartphone case that works without the need for batteries, wires, or even a Bluetooth connection.

The case is a purely mechanical creation, with spring-loaded buttons and dials (remember the Blackberry’s excellent scroll wheel?) that can be repositioned and reconfigured using a series of empty slots on the back of a device. Instead of using Bluetooth, wi-fi, or physically connecting to a smartphone’s sync port, the case instead relies on a device’s sensitive gyroscope to detect and translate button presses to events in the user interface.


GIF: YouTube

Grab your phone in one hand and press one of its volume buttons on the side, now that you’re paying attention you’ll notice that it moves around quite a bit in the process. The research team at Columbia University realised those movements could not only be detected by the gyroscope but could also be distinctly recognised, even amongst the motions of general usage of the device. The case’s buttons and scroll wheels, known as Vidgets, were designed to create very specific vibrations and tiny motions when used—which helps a custom piece of software to not only accurately detect them, but correlate their movements to something happening on screen. The research is detailed in a paper, “Vidgets: Modular Mechanical Widgets for Mobile Devices,” which will be officially presented at the Siggraph 2019 conference.

GIF: YouTube

Zooming a smartphone’s camera usually involves a two-finger pinch on the touchscreen, which not only requires two hands, but also means your fingers obscure the screen in the process. With this case attached, a user simply has to rotate a dial with their thumb to zoom in or out on a scene, and as the Blackberry taught us, that can be easily accomplished with just one hand.

The case could also vastly improve smartphone gaming. A touchscreen is a terrible way to play action games that require quick reflexes, or a joystick type controller. On-screen controls don’t provide any physical feedback, so it’s hard to tell if your fingers have slipped off a button in the heat of gameplay. With this case attached, the buttons and dials could serve as a physical controller, without requiring an overly obtrusive accessory strapped to your device.

The Vidgets aren’t quite a perfect solution for buttonless smartphones, or at least they aren’t yet. Overlapping button presses are rare, but vibrations from two simultaneous Vidget interactions, like pressing a button while a dial is being turned, can confuse the algorithm trying to detect them. And maintaining accuracy gets harder in situations where there’s a constant series of vibrations, like when a smartphone is used while riding in a car or on a subway. But the accuracy can and will be improved as the hardware inside smartphones gets more sophisticated to better track fitness and other physical metrics. Try as it might, a case like this could make it impossible for Apple to permanently take away my home button.