Today I sat in the sun to charge my watch. I kept my left wrist facing the sun. My right wrist was employed in keeping a kindle in place, reading.
My goal was to get the watch to go up by one day of charge and it worked. I wouldn’t sit in the sun to get a tan, but I would to charge a device. I didn’t time how long it took to charge but it wasn’t more than half an hour. In the middle of summer, in the right mode, I could easily see this watch charging a few percent a day in the right conditions. With the right combination you could get this watch to be autonomous.
A watch that doesn’t need to be taken off to charge is ideal, because it can track your moves for weeks, months or even seasons at a time. It also means that you can carry one less charger.
I am still reading A Good Place For Maniacs. He has finally left California behind.