The LG G Watch was the first one we tried that uses Google’s Android Wear OS (the Moto 360 and Samsung Gear Live do as well). It includes Google Now, the company's Siri-like "intelligent personal assistant." Say “OK Google,” and you can do Google searches, compose texts, and make requests of your watch (“Show me my steps” or “Set an alarm”). Google Now also offers up a stream of "cards" on the watch's face, with information it determines is relevant to you. If, for example, the card tells you how many minutes it would take you to get home from your current location, you can click on the card and get specific traffic and navigation information.
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. 
Smartwatches are relatively new gadgets, and their features are continuously improving. Each smartwatch needs to synch to your smartphone to get enhanced features. Once linked, depending on the model of smartwatch, you can forward emails, text messages, GPS directions and more to your wrist. Some smartwatches even have built-in microphones and speakers, allowing you to make phone calls. Calls are routed through your smartphone, just like when using a Bluetooth Headset. The Samsung watch—dubbed the Galaxy Gear—also has an integrated camera, so you can snap spontaneous photos without ever picking up your smartphone. Of course, ever smartwatch also functions as a traditional digital watch when not linked to a smart device. As the technology matures, expect to see more advanced features and perhaps even complete phone functionality built in.
Wrist watches have been fashion accessories since they were first invented. The first generation of smartwatches were dull, chunky looking devices, more functional than fashionable. How things have changed. You can select from thousands of watch faces and even design your own. Wrist straps can be swapped out and designers have come up with clever quick-release clasps for them, knowing that the need to charge your watch regularly will see you needing to remove it quickly.
Despite that, it's a very competent Android Wear 2 watch. What's more interesting, however, is the concentration on fitness.While it features all of the necessary sensors to track running, cycling and swimming, our initial testing has revealed the Huawei Watch isn't the stellar performer we hoped it would be. Which is a shame, because emphasising the fitness element was exactly the right thing for Huawei to do, and hopefully the company can improve its fitness tracking software updates.
Apple Watch Series 3: If you are an iPhone user and generally exist in Apple’s ecosystem, it makes sense to get an Apple Watch. The design quality is exceptional and the Watch makes a nice pairing with your iPhone as materials and design elements are common to both. Apple’s Health app covers most of the bases when it comes to tracking your essential fitness and activity indicators - nutrition, sleep, physical exercise, but Apple has gone further with HealthKit, which allows health and fitness apps downloaded from the App Store to share data with each other. Apple has committed to Watch, and its attention to practical and eye-pleasing design as well as useful tracking features is commendable. ($529)
Inside the Charge 3 are an accelerometer, gyroscope, optical heart rate monitor, and an SpO2 sensor for tracking blood oxygen levels. The Charge 3 is the third Fitbit device to include an SpO2 sensor, following in the footsteps of both the Fitbit Ionic and the Versa smartwatches. However, currently the SpO2 monitor lies dormant inside all of these devices as Fitbit hasn't made use of it yet.
Battery life and charging options: Charging your smartwatch is a hassle and the biggest downside to trading in your manually-wound or button battery-powered watch. A Fitbit Versa might last 3 - 4 days between charges, but a smartwatch like the Samsung Gear Sport or Apple Watch will need recharging every couple of days and sometimes every night if you are tapping on the screen regularly and using its apps.
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.
Apple has continued its focus on its health focus with the Series 4. In addition to being able to detect a fall, this new Apple Watch introduces three heart-rate tracking features that will be available later this year. It lets you know if your heart rate is too low, it can detect irregular rhythms (which may indicate atrial fibrillation), and most impressively, it serves as an FDA-cleared electrocardiogram.
The Huawei Watch 2 was one of the first smartwatches to launch with Android Wear 2.0 (now known as Wear OS), so delivers the handy Google Assistant straight to your wrist. Other improvements include more ways to respond to messages from your wrist, including a new on-screen keyboard. Wear OS doesn’t quite rival Apple’s watchOS for app support, but it has a decent stable of apps you’d expect.
At the 2016 Consumer Electronics Show, Razer released the Nabu Watch, a dual-screen smartwatch: integrates an always-on illuminated backlit display, that takes care of some pretty standard features as date and time, and a second OLED screen, which is activated by raising your wrist, allows access to extra smart features. Luxury watchmaker TAG Heuer released TAG Heuer Connected, a smartwatch powered by Android Wear.
There's now a heart rate monitor, as the name suggests, for tracking beats throughout the day and during exercise, a GPS monitor to keep up with your workouts and an NFC chip to enable Google Pay. Add to that the ability to take this underwater up to 50 metres, all on the top of the refreshed Wear OS, and it all rounds out as a very complete smartwatch experience.
It's also very bulky. Sitting at 46mm wide might not sound like much, but then you have the depth, and there's a lot of it here. In fact, if we had to pick one criticism of the Watch Sport it's that it crams so much in, it does so to its detriment. The size will be too overbearing for many, but the pay-off in size means that most of the great features of the Watch Sport have been discarded.
Fitbit Versa: The Fitbit is the health tracker for the masses and they have a model for every need. But the best option for adults who do a moderate amount of exercise and just want to keep tabs on their general fitness (ie: most of us), the Fitbit Versa is a great choice. It's an entry-level smartwatch. For more on the Fitbit Versa’s various attributes, read my in-depth review. ($350)
The Fitbit Versa is nearly a full smartwatch, but the way it handles notifications prevents it from being a pick. Fitbit’s sleep, step, and workout tracking features beat our current picks’, and in our testing the Versa regularly lasted for four or more days between full charges. It lacks GPS, which the Ionic has, but it has a lower price as a result. You can choose from a decent variety of band types, although the bands are an odd 23 mm size (rather than a standard 22 mm), and slot in at an angle, making it hard to know if an unofficial band will fit. You can cache Deezer or Pandora radio stations to the Versa’s 2.5 GB of reserved space, control the music on your phone (after reconnecting your watch in “classic mode”), or transfer your own music to the watch, though it’s a tedious process involving a computer and cable. Where the Versa falls short is in working with notifications from your phone. The notifications pile up, and it can be a hassle to clear them; most notifications don’t expand to show more text; and though a software update has given you quick replies to select from, you’re limited to five of them. Like the Ionic, it’s more of a smartened-up fitness tracker than a fitness-savvy smartwatch.
While internal hardware varies, most have an electronic visual display, either backlit LCD or OLED or Hologram. Some use transflective or electronic paper, to consume less power. Most have a rechargeable battery. Peripheral devices may include digital cameras, thermometers, accelerometers, pedometers, heart rate monitors, altimeters, barometers, compasses, GPS receivers, tiny speakers, and SD cards, which are recognized as storage devices by many other kinds of computers.
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.