The Samsung Gear S3 was our prior pick for Samsung phone owners because of its smooth dial rotation and interface. But it was notably large, with a 46 mm face, and the Frontier model was half an inch thick, notably bulky even for a smartwatch. The Gear Sport, our runner-up pick, is less bulky, less expensive, less overtly masculine-styled, and provides most of the same features, minus the LTE option.
But the Ionic, the first of Fitbit's devices to include an SpO2 monitor, came out more than one year ago. It's frustrating to hear about exciting features that are "coming soon," when "soon" ultimately means not weeks or months, but years. While I understand it takes time and effort to develop features like this (especially if Fitbit hopes to pursue medical device clearance or approval from the FDA in the future), I don't think Fitbit should hype features that it isn't ready to let users put to the test.
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.
The Apple Watch Series 4 is now on sale, and it's the best smartwatch you can buy right now. The redesigned device, which starts at $399 for the GPS model and $499 for the cellular version, is the best smartwatch you can buy. It has a larger display and slightly bigger case size while retaining the same rounded square design the watch is known for. Even more importantly, Apple received FDA clearance for a new electrocardiogram feature that can take a 30-second EKG and diagnose atrial fibrillation.