Further to your answer regarding the Citizen’s Eco-Drive watch: My Eco-Drive watch also has digital displays that stop functioning when there is no light (for example when my sleeve or hand covers the watch) and the second hand will stop at 12. The watch continues to function but in a slow down mode. When the watch is exposed to light, these functions return and the digital displays appear and the second hand goes to the correct time. Am I allowed to wear this watch on Shabbat and Yom Tov since when I cover and uncover the watch with my sleeve I start and stop the slow down mode?
Sounds to me like this watch should not be worn on Shabbat.