There are plenty of affordable smartwatches out there, but only a few are actually worth your time. The sub-$100 category has become the wild west of wearables; crowded with imposters making big claims and delivering on very few. We haven’t tested every bargain-bin watch on the market, but we’ve tested enough to know when we’ve found a rare gem. A watch that goes beyond just the basics, with solid health and fitness tracking, smartphone features that actually work, and a multi-day battery...