Benjamin Mayo, 9to5Mac:

The iPhone 8 is widely reported to feature a front-facing 3D sensor which will enable face recognition for automatic unlock (supposedly replacing the need for Touch ID entirely). Moreover, code references suggest that the new OLED iPhone will be able to use that same sensor to enable even more sophisticated features, like automatically silencing notifications if the user is looking at the screen.

This is based on the recent HomePod data leak, not a verified feature. That said, I love this idea. As a developer, I also love the idea of exposing this part of the interface, allowing me to take one action if the user is looking at their screen, another if they are not.