Google E-Screen Protector prevents peeping — or does it?

Google’s new E-Screen Protector prompts users when prying eyes are on their smartphone screen. Is this technology useful?

Does over-the-shoulder peeping annoy you? Same for us, and many others, too. In response, Google recently showed off a prototype app for Android that could help solve the problem of wandering eyes. How does the technology work — and are there any pitfalls?

To repeat: This is a prototype, so details are few and far between. We know that the new technology is called E-Screen Protector, and it uses a front-facing smartphone camera and machine learning to identify human eyes. If more than two eyes are detected in the camera’s field of view, that means you’ve got company.

According to the developers, the app needs an average of just 130 milliseconds to spot a smartphone voyeur. As soon as it does, the image from the front camera is displayed on screen with the onlooker’s face inside a red frame accompanied by the words “A STRANGER IS LOOKING ALERT!!!” Here’s how the prototype works:

What’s not to like? The technology protects your personal space and guards against peepers. But every silver lining has a cloud.

Security, anyone?

For the app to detect eyes with the phone’s front camera, said front camera must be on whenever you are using the phone. Moreover, the user must give the app permission to continuously process captured images, otherwise it won’t be able to detect a thing.

That raises a couple of questions. For starters, where will screen images be stored and processed? And who might gain access to them? These questions have already been asked about Apple’s much-hyped Face ID, used to authenticate owners of the new iPhone. Apple says that the images are stored in the encrypted memory of the Secure Enclave coprocessor, which had previously been featured in the news because of a vulnerability uncovered in it. (Sure, it was fixed right away, but who’s to say others won’t surface in the future?)

The same concerns surround Google’s new toy. If a vulnerability is lurking in the image storage system, questions of protecting personal space will fade next to threats to personal data. Not to mention, do you want Google filming you all the time?

Is it actually useful?

The issues aren’t only about the new technology’s security, but also its usefulness. In real life, most smartphone peepers simply won’t be picked up by the camera. The most common peeping occurs when someone is sitting next to you on public transport and sees what you’re doing out of the corner of their eye. At that angle, the camera won’t catch it. In this case, the app is just useless.

And what happens if you invite someone to take a look at your screen? You might show a friend a funny picture, for example. You and your buddy look at the screen together, the app spots an extra pair of eyes, and suddenly the picture turns into a live stream from the front camera with your friend’s face framed menacingly in red. That might need some explaining from your side.

So, this new widget is clearly not issue-free. Whether it gets the green light and becomes part of Android remains to be seen. Google plans to officially unveil the technology at the 2017 Neural Information Processing Systems conference, scheduled for December 4–9 in California, so by that time we’ll probably get some more details.