It quickly emerged that face unlock on the Pixel 4 and Pixel 4 XL does not detect if your eyes are open after Google Made by 2019. Days before the shipping of the flagship starts, Google announced that a future update will include eye detection.
The current failure of the Pixel 4 to detect if your eyes are open makes it trivially easy for somebody to pick up a sleeping person’s phone — hypothetically. There is absolutely no physical contact needed compared to unlocking fingerprints to open your phone, access information, or accept payments. Official guidance from the company is to “keep your phone in a safe place,” but it’s not always possible.
Google confirmed to The Verge this evening that it’s “been working on an option for users to require their eyes to be open to unlock their phone.” Oddly, Pixel 4 face unlock “eyes open” preference can be seen today on Pixel 3 by searching for “eyes” settings.
The option for eye detection will be officially “delivered in a software update in the coming months.” Due to the longer time frame stated, the preference will certainly not be available while shipping, and the November security patch will probably be missing in two weeks. Whether it’s going to be ready in time for the December update is unclear.
At the keynote, Google stated to unlock the face much faster by adding Motion Sense to kick off the process when you hit your phone. There is an inherent tradeoff in the implementation of the Pixel 4 between speed and absolute security.
Google suggests using “lockdown” to disable face unlock until a pin or code has been entered for those concerned. It can be enabled from Settings > Display > Lock screen display > “Show lockdown option.” If you press the lock button for a long time it will appear in the power menu.