Word of mouth: retailers in China have been using face recognition technologies to identify key customers so that they can be greater by name when delivered their favorite drink upon entering the premises.
The trouble with "word of mouth" is that you can't tell whether something is actually real, or vaporware that some account executive dreamed up to close a deal.
I agree, which is why I qualified it. I was working at a retailer, building it's cloud systems at the time. It was told to me by a colleague who claimed to be told that by a peer from China at a conference.