Plugging that directly into an iPad or MacBook seems some combination of risky and awkward. But that's fine, you don't have to use it that way.
Personally I would have designed it with a "female" USB-C connector so that any USB-C cable would work.
In other words, I would have made it like Apple's optional charging dock, with USB-C instead of lightning as the connector.
-watch-magnetic-charging-dock?fnode=80
In any case, $45 for this would have been a better purchase than the $80 I (my wife) spent on the Apple version.
Update: I hadn't realized that Apple has introduced a $29 USB-C Watch charger (as mentioned at the end of the article). I don't know why anyone would spend $45 on a third party version when Apple sells an equivalent product for less. (Again, I would be concerned about plugging it directly into any device without the cord; USB-C ports are not design to bear any weight/strain.)