I’ve worn a smartwatch almost daily for nearly five years as of this writing. I often feel that it keeps me alert to what’s happening, especially for things like texts from my wife and close friends, alarms that a parking meter is nearly expired, or reminders that dinner needs to start marinating or roasting. It has also encouraged me to get moving and take a walk when I’d otherwise stay in place. Sometimes it has made me feel rude, distracted, or overly attached to whatever little blip comes next. It has come in handy on my bike, and it has distracted me when I’m driving my car. Some of this can be better handled through settings and filters, but some of it comes from human nature.

That’s the big downside of relying on your phone as a tracker, unless it is somewhere on your body, whenever you are moving about or exercising, all that effort won’t be counted. For some people - say joggers who wear their smartphone on an arm band, that’s not a big issue, but you really aren’t getting the full picture of your activity, including the things you do in your sleep, without having a gadget mounted on your wrist.
Its only drawback is its use of Samsung’s own Tizen OS. Tizen is a custom OS that’s based on Linux. On paper it’s pretty good, letting you pair the Gear S2 with any Android smartphone, not just Samsung Galaxy phones. But it’s nowhere near as developed as Wear OS, which itself isn’t perfect. There aren’t nearly as many apps available as the Wear OS app store, but the core functionality is at least present from what is available.
In June 2000, IBM displayed a prototype for a wristwatch that ran Linux. The original version had only 6 hours of battery life, which was later extended to 12.[20] It featured 8 MB of memory and ran Linux 2.2.[21] The device was later upgraded with an accelerometer, vibrating mechanism, and fingerprint sensor. IBM began to collaborate with Citizen Watch Co. to create the "WatchPad". The WatchPad 1.5 features a 320 × 240 QVGA monochrome touch sensitive display and runs Linux 2.4.[22][23] It also features calendar software, Bluetooth, 8 MB of RAM and 16 MB of flash memory.[24][25] Citizen was hoping to market the watch to students and businessmen, with a retail price of around $399.[25] Epson Seiko introduced their Chrono-bit wristwatch in September 2000. The Chrono-bit watches feature a rotating bezel for data input, synchronize PIM data via a serial cable, and can load custom watch faces.[26]
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.
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.
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. 
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