If Apple is hard at work on an "iWatch," it will have to overcome battery issues bedeviling existing smartwatch makers.
This new crop of wrist devices has a lot more in common with smartphones than your old Timex. They have increasingly large displays, and can ferry over notifications and other data, acting as a second screen of sorts for your smartphone. For many of the latest models, that extra utility is not without a compromise: You've got to plug it in at the end of the day.
Charging a smartphone every day can be an annoyance, but … Read more