While Face Unlock on the Pixel 4 is definitely an improvement over both physical and in-display fingerprint scanners, Google’s 3D face scanning biometric isn’t all it could be. For one, it has limited app support, but even for simple unlocking, there’s a flaw that could allow someone to unlock your phone without your permission. A new feature rolling out as part of the April Security Update fixes that.
Once the update hits your phone this week, a new toggle will appear inside the Face Unlock tab in the Device Security settings. It’s called “Require eyes to be open,” and as the name suggests, it won’t unlock your phone unless your eyes are open. That means if you’re sleeping someone can’t get into your phone and if you just want to keep someone out, all you need to do is close your eyes.