Pebble was a smart watch which was not tethered to a phone, talked to the cellular network directly, and had battery life problems, correct? Apple's smart watch was tethered to a phone, so it needed less power.

It's going to be interesting to see what happens when solid state batteries become available and increase how much energy you can store in a watch. They're high cost, but if you're powering a watch, not a car, probably affordable. That could make standalone watches more effective. Maybe eliminate the need to carry a phone all the time.