You won’t get much use out of an Apple Watch if you don’t have an iPhone nor any other kind of iOS-enabled mobile device. The same thing goes for the Samsung Gear Sport. While the Q Venture does feature some compatibility with Android and iOS devices, it won’t mix well if you’re a Samsung customer. The smartphone you use will ultimately determine which smart watch you get the most value from.
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.
The RC-1000 Wrist Terminal was the first Seiko model to interface with a computer, and was released in 1984.[10] It was developed by Seiko Epson and was powered by a computer on a chip.[12] It was compatible with most of the popular PCs of that time, including Apple II, II+ and IIe, the Commodore 64, IBM PC, NEC 8201, Tandy Color Computer, Model 1000, 1200, 2000 and TRS-80 Model I, III, 4 and 4p. The RC-20 Wrist Computer was released in 1985, under the joint brand name "Seiko Epson".[13][14] It had a SMC84C00 8-bit Z-80 microprocessor; 8 KB of ROM and 2 KB of RAM. It had applications for scheduling, memos, and world time and a four-function calculator app. The dot-matrix LCD displayed 42×32 pixels, and more importantly, was touch-sensitive. Like the RC-1000, it could be connected to a personal computer, in this case through a proprietary cable. It was also notable in that it could be programmed, although its small display and limited storage severely limited application development.[10] The RC-4000 PC Data graph also released in 1985, was dubbed the "world's smallest computer terminal".[10] It had 2 KB of storage. The RC-4500 (1985), also known as the Wrist Mac, had the same features as the RC-4000, but came in a variety of bright, flashy colors.

I've been pleased to see swim-tracking trickle down into more affordable devices over the past few years. Fitbit's Flex 2 remains its most affordable device with swim-tracking features, priced at $60. But the $150 Charge 3, with its big display and smattering of smartwatch capabilities, is for a different audience than those who would gravitate to the tiny, quasi-cylindrical Flex 2. Even if you don't swim often, water-resistance up to 50 meters means users don't have to worry about showering with the Charge 3 or dropping it in the pool by accident.

The Series 4 now has several new health-focused features, which are very intriguing, including the ability to detect when you fall and even alert emergency contacts if need be, as well as an electrical heart rate sensor that works with an app to alert you to heart health issues. The electrocardiogram (ECG) app has been certified by the Food & Drug Administration, but it's not out yet.
The Apple Watch boasts cutting-edge smartwatch tech including mobile payments with Apple Pay, stand-alone GPS, full waterproofing up to 50 meters, and thousands of apps. The user interface is very simple and attractive. It's easy to use and it has advanced, easy-to-use fitness tracking features, thanks to a plethora of sensors and an excellent heart rate monitor.
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.
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.