The Apple iPad is the epitome of minimalist design. It can host a wide range of apps and functions all within its slim frame and function perfectly using just one home button and touchscreen technology. But this minimalism has its drawbacks when you want to use more complicated applications that require toolbars within the app. This was the challenge faced by developers at Astro when they began work on their new app, Luna Display. The app is designed to let your iPad become a wireless second touch screen display using a small dongle. The team was looking for a way to allow users to pull up the screen setting within the Luna app, but they didn’t want to add extra UI and of course, the iPad offered no additional interface to use. But then they came up with a totally revolutionary idea.
The Camera Button
The Astro team hacked the iPad's front-facing camera and made it into an extra button. Simply tap the camera lens and the Tools menu appears. Tap it again and the menu disappears. Astro HQ cofounder Giovanni Donelli describes how the idea came to them like a bolt of lightning, “I had been staring at a white bezel iPad for so long, and I kept wishing there was another home button we could use. My eyes kept falling on the camera, and I really wanted to touch it!”
Astro is calling the button ‘the camera button’ and it works by measuring the amount of light that is hitting the camera lens. When light is totally blocked by your finger the iPad responds by popping up the menu. Open the camera to light again and the menu disappears.
The team had to go through months of grueling testing to figure out how to get the camera button to work in all lighting conditions and across all iPad models.
Astro have given some great insight into their design process in a blog post on Medium. They unpack the way they built a makeshift lightbox that allowed them to manipulate lighting to text under a variety of conditions. Turning the camera into a button requires the camera to be processing the whole time the app is being used. This poses two problems, the first is battery life and the second is privacy. From the beginning, these were both priorities for the Astro team. To reduce the drain on the battery, engineers developed efficient code that resulted in the camera button only using 1% CPU. But an even more important issue for many users is the matter of privacy.
In an age when hacking is commonplace and your webcam might even start talking to you, ensuring that you aren’t making it easier for people to access your camera is of utmost importance. To overcome this, Astro created a way for the camera to blur images to a point where not recognizable data is coming in. The camera, when used as the button, is only registering light. In addition to this hack, the data that does come is never sent to a server. But for some, even these tight solutions aren’t enough, and so for the very safety conscious, the camera button functionality has also been incorporated into the iPad volume control buttons.
The hack is ingenious and opens the possibility for other apps to develop toolbars that take advantage of the Camera Button.