Face ID is great, as long as your iPhone can see your face. A mask — like the ones we all should be wearing to slow the coronavirus pandemic — blocks the iPhone’s Face ID sensor from seeing your face. That means you either need to remove the mask (bad) to unlock your iPhone, type in your passcode every time (annoying), or disable the passcode entirely (a terrible idea).
But, according to in-depth research from China’s Tencent Xuanwu Lab, you can train Face ID to work while you’re wearing a mask. It needs some careful setup, but once it’s done, it works reliablly and quickly. You can even wear glasses.