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. 
Receive Texts, Emails, And Alerts Without Reaching For Your Phone/ Military-Grade Gear S3 Is Tough Enough To Handle The Elements/ Built-In S Health App, Track Your Steps, Monitor Your Heart Rate, And More/ 4GB Internal Memory/ RAM 768MB/ Wi-Fi/ Bluetooth 4.2/ Gorilla Glass SR+ Case Crystal/ 1GHz, Dual Core (Exynos7270) Processor/ 360x360 Display Resolution/ On-Cell Touch AMOLED Touchscreen/ GPS Navigation/ Dark Grey Finish
When you do switch to the OLED display, you are in TicWatch Pro’s Smart Mode, and you can perform all of the features and functions that are available in the smartwatch. However, switching to the low-power FTSN LCD display puts the watch in its Essential Mode. The nice thing is that when you switch back to Smart Mode. all of the heart rate and steps info gathered by the watch’s Essential Mode are synced up and transferred to the onboard Wear OS. As you might expect, the battery life in Essential Mode can last up to 30 days, while using the smartwatch in Smart Mode cuts that battery life down to just two days.
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.