Yeah, but there's a particular flowchart with a watch that doesn't look like a Pebble. Not that it's a dead giveaway, but it is definitely Apple being a little more future-documenting than in the past.
If so I think you're reading into it too much. It looks like a generic watch, the way watches have looked ever since watches came on wristbands. It just seems like generic clip art where it's clear to the reader "that's an iPhone, and this is a wrist device."
https://developer.apple.com/library/ios/documentation/CoreBl...