Re: Innovative sundials?
"To be fair, analogue watches don't work in the dark either."
Yes they do, they glow in the dark. Have done for a very long time.
Also there have been analogue watches that have a backlight around for long enough that you can buy one for your kid:
https://www.amazon.com/Watches-Analog-Waterproof-Backlight-Children/dp/B076GZ3PJY/ref=sr_1_3?ie=UTF8&qid=1550510926&sr=8-3&keywords=Analog+Watches+With+Backlight
Here is another analogue watch that sets the time by itself from a radio broadcast powered by an atomic clock, this also lights up in the dark:
https://www.watchshop.com/mens-casio-g-steel-bluetooth-triple-connect-chronograph-radio-controlled-watch-gst-b100d-1aer-p100014520.html
As that one too expensive? Here is one using Indeglo, a backlight trademark that came out in the 90's:
https://www.watchshop.com/mens-timex-indiglo-expedition-watch-t49713-p99946837.html
So yes, analogue watches work in the dark and have done so for a number of decades.