For a device that gives you more of the functionality you enjoy with your smartphone, you’ll want to opt for a dedicated smartwatch. The leading players at the moment are the Apple Watch for iPhone users and the Samsung Gear S3 for those with Android phones. Apple Watch has its own operating system, Samsung employs its Tizen OS, and a host of other smartwatches use the Google Wear operating system.
The build is fantastic with IP68 waterproof and Corning Gorilla Glass DX+, and the display looks great with a resolution up to 360 x 360 and Circular Super AMOLED tech. On the larger model, the battery sports a capacity of 472 mAh, which powers the snappy Exynos 9110 Dual core processor. You can choose between Silver, Midnight Black, or Rose Gold color options, and the bands are interchangeable to match your style. But most importantly, with the Tizen-Based Wearable OS 4.0 that Samsung has optimized to work with their proprietary controls and apps, this will be the perfect sidekick to your Samsung phone.
As a piece of hardware, the Gear Sport is probably the best smartwatch we’ve used. It’s not stylish, it has deep flaws in its voice software, and it’s only a beginner-level fitness tracker. But if you want a smartwatch that has a bit of fitness motivation—and if you also happen to have a Samsung phone, or might get a deal on a bundle of phone and watch—the Gear Sport is a good option.
The Samsung Gear Live is the first of the company’s smartwatches to be compatible with any Android phone running Android 4.3 or higher; other Gear models can be paired only with specific Samsung phones. Like the LG G Watch and Moto 360, it runs the Android Wear OS, allowing voice commands and pushing relevant information to the wearer. Compared with the LG G Watch, we prefer the style and fit of the Gear Live. The watch body is slightly curved, which made it more comfortable. The Gear Live also has a heart-rate monitor, which the G Watch lacks.
Apple is back with the Apple Watch Series 4, the latest in the smartwatch game that's focused on helping wearers live a healthier lifestyle. Running on Apple’s S4 64-bit dual-core processor and the new WatchOS 5 operating system, it’s twice as fast as its predecessor. Available in two sizes — 40 mm and 44mm — it has a 30 percent larger display than the Series 3 and comes in six different aluminum and stainless steel finishes. New improvements include Walkie Talkie mode and a speaker that is 50% louder than in the Series 3. The microphone has been moved to the watch’s opposite side to reduce noise and create clearer phone calls. The bottom, now made from black ceramic and sapphire crystal for better radio wave transmission, is intended to help with cellular reception and call quality.
To round off the Gear Sport’s positives, it has very solid battery life (almost never less than 50 percent of the battery remaining after a full day), it can play offline Spotify playlists (even for free accounts), and if you have a Samsung phone, it integrates easily with most of the apps you have installed there. The Gear Sport is easier to set up with a non-Samsung Android phone than previous versions of the Gear watch, too. It still requires the installation of at least four apps and some regular updating, but it’s not the hour-long trial-and-error of other Gear watches we’ve tested, working reliably in our testing.
Wear OS comes with a focus on fitness features, but unfortunately Huawei managed to simultaneously move too far in this direction and also fall short of it. It doesn’t come with a rotating side button for navigation, which is a shame as we really love the button on the LG Watch Sport. It does, however, come with great battery life and a stellar feature set otherwise.
The top smartwatches that debuted at the 2017 Consumer Electronics Show included the Casio WSD-F20, Misfit Wearables Vapor and the Garmin Fenix 5 series. Apple released on September 22, 2017 their Apple Watch Series 3 model which offers built in LTE cellular connectivity allowing phone calls, messaging and data without relying on a nearby smartphone connection. 
The Gear S3 also offers a dual-core Exynos 7270 processor, 768MB of RAM, and 4GB of storage. The watch also features sensors such as GPS, NFC, and even optional LTE. The standout features, though, include Samsung Pay (on any smartphone) and the rotating bezel. The Gear S3 is a pretty big watch, though, coming in at 12.9mm thick with a 46mm diameter.
You can also use devices that support the Google Wear operating system in conjunction with an iPhone as well as a Samsung Gear device that runs Samsung’s own Tizen operating system. But Google Wear and Tizen devices are designed to pair with smartphones using the Android OS, so you won’t get full functionality when pairing with an iPhone. For instance, some Android smartwatches carry Samsung’s smartwatch line-up and naturally enough, work best with Samsung smartphones, but are still compatible with Android-powered Huawei or Nokia phones.
On-Screen Workouts/ Connected GPS/ Bluetooth/ Smartphone Notifications/ 4 Day Battery Life/ Heart Rate Tracking/ 15 Exercise Modes/ SmartTrack/ All-Day Activity/ Female Health/ Sleep Tracking And Stages/ Cardio Fitness Level/ 3-Axis Accelerometer And Gyroscope/ Optical Heart Rate Monitor/ Color LCD Touchscreen Display/ Water Resistant To 50 Meters/ Grey And Silver Aluminum Finish
Wear OS’s chief problem, as we see it, is that it relies too much on input from swipes, taps, and other finger gestures. On a largish screen, such as on our top pick, this is less of a problem, but on smaller devices, trying to hit just the right button on the screen is like playing a very small version of Duck Hunt. The Apple Watch, by comparison, makes most of its buttons screen-wide rounded rectangles, which are easier to hit. On newer watches with three buttons, Wear OS also doesn’t utilize the physical controls beyond the home display (watch face), where they serve as shortcuts to apps or a list of apps.
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 touchscreen, button, and dial (what Apple calls the “crown”) help you zoom in and out and move between apps fairly effortlessly. With this easy navigation it’s easy to forget we’re typing on a screen slightly smaller than an Oreo. In particular, we loved Apple’s app homepage, which displays all of the apps as icons in a honeycomb-like display. You can use the touchscreen to move around, and the dial to zoom in or pan out, to precisely tap on the one you want.