I was under the impression that the true depth camera system only operates whilst using Face ID (unlocking, Apple Pay etc) and whilst using Animoji. However, I then wondered how the attention features worked i.e. not dimming the display while looking at it and reducing the volume of alerts. Apple state on their website: ‘Even if you don’t enroll in Face ID, the TrueDepth camera intelligently activates to support attention aware features, like dimming the display if you aren't looking at your iPhone or lowering the volume of alerts if you're looking at your device. For example, when using Safari, your device will check to determine if you're looking at your device and turns the screen off if you aren’t. If you don’t want to use these features, you can open Settings > Face ID & Passcode and disable Attention Aware Features’. I’m not worried about the health concerns around Face ID as I personally don’t believe it to be an issue. I’m just curious how it works. Anyone with more info?