According to Huawei, the 400mAh watch battery lasts up to 10 days, although with typical usage, it’ll be closer to a week. In any case, it won’t need charging anywhere near as often as a phone.

Despite how vital it is to our existence, most of us rarely think about our heartbeat until, say, a surge of adrenaline causes it to flutter in our chest. Beats are also faster in moments of stress or ...