Dropping the phone: Some models of smartwatches in the Samsung and Apple line-ups feature a mobile network chip, allowing you to plug in a micro SIM card to make and receive calls, texts and emails and access the internet without being paired to your phone. It sounds great, but remember that the smartwatch has a very small battery, so relying on it for communications will drain the power quickly.
Samsung treads between smartwatch and fitness tracker, also packing in a heart rate sensor along with that GPS and its much-improved Samsung Health software. There's also the option of LTE (coming soon), if you wish for an untethered connection, with a standalone speaker for taking calls on the watch. It's now waterproof, too, adding swim tracking skills that are on par with the Watch Series 4.
Our top pick for most people is the Apple Watch Series 4 with GPS (starting at $399), which has a huge display, ultra-fast processor, Raise to Speak Siri, fall detection and a built-in electrical heart rate sensor for taking on-the-go electrocardiograms. It also runs watchOS 5, which makes the watch even more useful with automatic workout-tracking, offline podcast playback and a Walkie-Talkie voice chat feature.