Why does anyone need to charge a smartwatch on a bus? They charge very quickly and last for days. A Pine64 is not much more expensive, and works with the Gadgetbridge app, and is open (there is even a choice of two OSes). It works with Gadgetbridge so the app does not have all the same functionality and also has rough edges (but so does any cheap smartwatch). I even prefer the charger as its a magnetic cradle so the watch snaps into place when placed on it.
Not only the smart watch, but a hundred other gadgets including a toothbrush. Presumably this process involves bringing a USB hub onto the bus, or else the bus is not the main point here. I think it's like I want to be able to charge my watch on the bus if I feel like it.
A smartwatch is very different from a phone. its less important to have it working, it charges faster, and the battery lasts a lot longer - several days of normal use is typical.
