The operating system you choose depends solely on the type of smartphone you have because the smart watch is paired with your smartphone. If you own an Android smartphone, your smart watch should have Android Wear or Tizen. If you own an iPhone, choose an Apple Watch. For example, the Samsung Gear S3 runs Tizen and is compatible with both the Android and iPhone.
But your phone will play an important part if you do get a Fitbit or Garmin device with the aim of tracking your activity. It will be the place where your health data is synced to, you can tinker with your tracking settings and review your progress. There’s also a whole ecosystem of health apps that plug into tracking devices, combining them with exercise and diet advice - MyFitnessPal, Runtastic and Strava are three of the most popular ones worth checking out.
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.
If you’re trying to decide which one is right for you, allow us to help. The Versa is smaller and looks good on most wrist sizes, while the Ionic is probably best for large wrists. The other main difference is GPS connectivity — the Ionic comes with built-in GPS, while the Versa does not. However, you can pair it with your smartphone if you don’t mind bringing it with you on a run.
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 Watch (1st generation and Series 1) Apple watchOS No 8.2+ (1st generation) 10.0+ (Series 1) Apple S1 (1st generation) Apple S1P 4.0 LE ] From paired iPhone No Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes No Yes Yes IPX7 Digital 1.7 / 1.5 319x390 / 272x340 AMOLED 1.5 250 / 205 Lithium-ion 42 mm / 38 mm 12.46 / 12.3 36.2 / 32.9 Varies Yes Yes No
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. 
These new smartwatches build on a pretty familiar package. Both are powered by the Qualcomm Snapdragon Wear 2100 processor and run on Wear OS. Both also get GPS, NFC for Google Pay, and heart rate sensors as well. The Venture is the smaller of the two, measuring in at 40mm with an 18mm band. The Explorist, on the other hand, is a 45mm watch with a 22mm band.
Unfortunately, you won't be able to respond to alerts (like messages and emails) from the Charge 3. That's a feature sequestered to smartwatches, but you can see most of the content of an alert on the device's screen. Considering how narrow the device's screen is, reading through a long email won't be the most comfortable experience. But at least that message will be glanceable on your wrist, as will news headlines, text messages, and other alerts as well.
Many major phone apps have Wear OS counterparts, or at least most apps that make sense to have a dedicated watch app. You’ll likely find yourself using most watch apps less than you might think, but they are sometimes convenient for avoiding a phone retrieval. I use regularly use the Nest app for my home thermostat, Keep to take down a quick voice note, PocketCasts to control podcast episodes and playlists, and Stronglifts to time and track workouts. But I use these on my watch mostly when my phone is not at hand; none is easier to use than its phone version. As noted, most apps on your phone will provide notifications that can be acted upon through your watch. For the apps that you do use, the Q watches’ screen (identical to most of the Fossil group watches’ screens) is responsive enough to work with tiny buttons pressed by big fingers.
This watch won’t work unless you have an iPhone. However, it is hands-down the best smart watch for an iPhone. Other watches (including the Fossil Q Venture) will work with an iPhone, but won’t be able to answer calls or respond to texts, and if you want to customize the apps on your watch, you’ll need to navigate the Google Play store through the watch screen.
Google confirmed to Tom's Guide that the company won't be releasing its own Wear OS smartwatch this year. The news comes after months of rumors that a Google-branded Pixel Watch running on Qualcomm's latest processor would be launched at Google's October hardware event. Instead, Google plans to focus on adding features to Wear OS on the software side and support the companies who are currently making Android smartwatches. Google's hardware event is Oct. 9.