The iPhone X's new feature where it approximated you facial expressions on a 3D character using the facial recognition sensors blew my mind as well.

It was a party trick. I can't remember the last time I touched it. That's what SORA is, or was.

While Apple use of the tracking was not more than a party trick, the foundational technology they created for this is currently the best low budget tracking solution and heavily used in VTubing (online streamers that use an Avatar with live facial tracking instead of showing their face via webcam)

I know the developer who worked on it took pride in the outcome. Hopefully they added some additional characters to keep it fresh.