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iPhone X’s Face ID has at least 3 cool hidden features

And I'm not just talking about selfie portraits or animated poop.

You probably know that Apple's new Face ID feature will unlock the iPhone X and secure mobile payments with Apple Pay. You might even know that the front-facing camera behind Face ID can apply portrait mode to selfies and also breathe life into animated emojis, or "animoji."

But did you know that Face ID knows when you're looking at the screen, and then makes the iPhone X respond?

According to Apple's website, when you're looking at the screen, Face ID will:

  • Reveal notification and messages for your eyes only
  • Keep the screen lit when you're reading (don't you hate when it dims before you're ready?)
  • Lower the volume of an alarm or ringer, because you can hear it, already, I mean, you're right there

Apple isn't the first to keep the screen lit when you're reading; an optional Samsung feature called Smart Stay has done the same since the Galaxy S3 in 2012. Apple's Face ID takes it a step further by linking notifications and ringer volume to your eyeballs (hopefully this won't drain your battery too much in the process).

This subtler part of Face ID is the type of context-aware AI that devicemakers have been struggling to make people care about. For example, the HTC U series has included AI meant to learn your behavior and surface info like notifications for things you care about most. 

Huawei's Honor Magic purported to use the phone's sensors to know who you were, what you were doing and what you wanted next. This kind of background AI so far hasn't caught on, and frankly works with varying levels of success, but it's also something that could quietly become a mainstay for phones in the not-too-distant future.

Apple's least-flashy use for Face ID may be its most convenient for phone owners, because in order to benefit from it, you won't have to do anything at all.

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