The Fitbit Ionic works fine as a Fitbit tracker, but despite being more expensive than our picks or the Apple Watch Series 1, it lacks many smartwatch functions you’d hope to have. It passes notifications from your phone to the watch, but you can only respond to some of them (with only five quick reply lines); and dismissing them (either one by one or as a group) involves annoyingly hard presses and long scrolls. Syncing music files and offline Pandora playlists requires you to use a desktop app, which is laborious. Two Wirecutter writers who tested the Ionic also had trouble setting it up to work with their Android phones (a 2015 Moto X Pure and a 2016 Samsung Galaxy S7) and had to perform significant troubleshooting to get their data to sync. The Ionic’s battery life, even while using GPS for outdoor exercise tracking, is its most impressive feature, lasting at least five days in one test and nearly seven days in another. The Ionic is most useful to Fitbit enthusiasts who want to track outdoor exercise without bringing a phone; it’s not a good option if you’re looking to deal with incoming information.
The company claims that the SpO2 monitor will help its devices look for signs of sleep apnea and other breathing problems, potentially great features for devices that are meant to be worn 24/7. It'll be used primarily in Fitbit's forthcoming Sleep Score Beta, which further analyzes sleep quality using heart rate and breathing data. Starting sometime this November, users with devices that only have heart rate monitors can get a "sleep score" after each night's sleep. Those with an Ionic, Versa, or Charge 3 will presumably have better data thanks to the SpO2 monitor collecting breathing data.
Garmin, known primarily for its GPS and fitness devices, has taken one step closer to full-featured smartwatches with their Vivoactive 3 Music. This model doesn't run on Wear OS (Google's increasingly-popular OS for wearables), but it does offer thousands of free apps, watch faces, and more via Garmin’s ConnectIQ store. The Vivoactive 3 Music also comes preloaded with 15 sports apps to monitor your progress whether you're running, swimming, lifting, or doing yoga — because, at its core, Garmin is still all about fitness tracking
The Amazfit Bip is thin and light, looks like an Apple Watch, has a lot of sensors inside—GPS, heart rate, accelerometers, barometer, and compass—and can run for about 30 days (which we confirmed) between charges, all for around $100. Those facts are compelling, but actually using the watch is frustrating, and it doesn’t do any one thing well. The GPS and heart-rate monitors can be slow to start, sometimes drop out, occasionally have wild inaccuracies, and produce results notably different from those of running watches and dedicated fitness bands. The screen is also dim and noticeably low-resolution, and the phone software for managing the watch is dense and unintuitive on Android. (We didn’t test iOS, but the reviews imply that it’s not much different.) The watch materials are plastic and rubber, and look and feel like it. Those are all trade-offs you could reasonably make if you just wanted a Pebble-like smartwatch that tracked steps and showed notifications, but even there, the Bip does not succeed: It often dropped connectivity with my phone (a Pixel 2), and it cannot show emoji—getting a dozen blank squares when someone sends you a thumbs-up sign is not helpful. If all you care about is battery life, the Bip has that, but it lacks useful functions while it’s charged up.
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.