Using your face to unlock your smartphone has been around a long time on Android, and it's used by many for its convenience over typing in a PIN or a password. With the right amount of lighting, it can even be almost as fast as fingerprint unlocking. Android's face unlock has suffered from some embarrassing mishaps, though, such as being fooled by a fake head or even just a regular 2D photo of your face. With the Pixel 4, Google is upping its game when it comes to face unlock security and speed. In addition to being secure enough now to process payments and log into apps, the Pixel 4 can recognize your face from any orientation, even upside down, and it does so very quickly.