Basically, smartwatches are wearable-technology devices that maintain a relatively persistent wireless connection to your mobile device—usually a smart phone—and can receive notifications of incoming calls, texts, instant messages, social-network updates, and more, from that device. Some can also let you accept and conduct phone calls right on the watch. And even newer models (the Samsung Gear S, for one) can act as smart phones all on their own, without needing a paired phone nearby.
I go for a middle-of-the-road approach—I enable alerts for most of my installed apps, save for ones that are niche (mostly shopping apps that alert me to coupons) or ones I don't use regularly. All alerts make the Charge 3 vibrate and show the message on its screen, and all past alerts live in the notification drawer that you can access by swiping down from the top of the Charge 3's display.
For all of you outdoorsmen, Casio returned to IFA this year with its latest Pro Trek watch. The Casio WSD-F30 takes the same great features of previous generations and slaps them inside of a slightly slimmer body. The 60.5mm × 53.8mm × 14.9mm body is still pretty huge, but it’s considerably smaller than what came before it and still maintains 5ATM water resistance, MIL-STD-810, and even low-temperature resistance.
Fitbit OS 2.0 brings a new-look UI that offers more insights into your daily data and quick reply support for messages for Android phone users (iOS support coming at a later date). You can still download apps and a whole lot of watch faces, pay from your wrist using Fitbit Pay and tap into Fitbit Coach, while new women's health tracking has also been introduced for the first time, which is also available for the Ionic, too.
In 2013, the claim to first ever smartwatch to capture the full capability of a smartphone was laid by startup Omate with the TrueSmart. The TrueSmart originated from a Kickstarter campaign which raised over 1 million dollars, making it the 5th most successful Kickstarter to date. The TrueSmart made its public debut in early 2014. Consumer device analyst Avi Greengart, from research firm Current Analysis, suggested that 2013 may be the "year of the smartwatch", as "the components have gotten small enough and cheap enough" and many consumers own smartphones that are compatible with a wearable device. Wearable technology, such as Google Glass, may evolve into a business worth US$6 billion annually and a July 2013 media report, revealed that the majority of major consumer electronics manufacturers were undertaking work on a smartwatch device at the time of publication. The retail price of a smartwatch could be over US$300, plus data charges, while the minimum cost of smartphone-linked devices may be US$100.
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 Martian Passport wants to give you the best of both watch worlds, by offering a mechanical, analog watch face and a small LCD. If you prefer a traditional-looking watch and want the “smart” component to be unobtrusive, this model may work for you. It comes in three varieties, all with silver bezels: a white face with a black or white band or a black face with a black band.
We loved Samsung’s characteristic bezel navigation. Instead of having to swipe your finger across the touchscreen repeatedly, all you have to do is gently twist the bezel. It’s a much smoother way of scrolling through your list and it just feels more natural. The are other side buttons which lie almost flush with the side of the watch, making it difficult for them to catch on sleeves.
Apple has announced the Apple Watch Series 4. It’s the first real redesign of the wearable since Apple introduced it in 2014, but the changes aren’t so drastic that you won’t recognize it as an Apple Watch. The Series 4 comes with an upgraded display, and you can choose either a 40mm or 44mm model. Even though the screens on the new models are bigger, the overall body of the Watch is roughly the same as previous models, so you shouldn’t notice much of a difference on your wrist.
Smartwatches, like smart phones, can also run apps, via your smart phone or right on the watch. These include health and fitness apps (thus the comparison with activity trackers), apps that control functions such as music and the camera on your phone, navigation apps, and more. Because most smartwatches have open software platforms (at least so far), developers are coming up with new and innovative apps that can increase the functionality of the devices.
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.