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.
That same attractive stainless steel design is here. The 240 x 240 pixel display at the heart of the body is by no means the brightest or most vibrant you'll find, but crucially delivers strong visibility in most workout conditions whether you're sweating it out indoors or outside. However, there is no touchscreen or touchpad here, you'll have to resort to pressing some buttons - that could be a deal-breaker for some, but we're sure it won't be a massive one for most.
The LG G Watch was the first one we tried that uses Google’s Android Wear OS (the Moto 360 and Samsung Gear Live do as well). It includes Google Now, the company's Siri-like "intelligent personal assistant." Say “OK Google,” and you can do Google searches, compose texts, and make requests of your watch (“Show me my steps” or “Set an alarm”). Google Now also offers up a stream of "cards" on the watch's face, with information it determines is relevant to you. If, for example, the card tells you how many minutes it would take you to get home from your current location, you can click on the card and get specific traffic and navigation information.
Although rectangular is the most common design, there are smart watches that have a circular display similar to regular watches. The Apple Watch is only available in the rectangular design. The circular design is available in the Samsung Gear S2, Moto 360, and LG G Watch R models. Many models have changeable straps, so you can dress casual, sporty, and formal.
For deeper integration with your Android phone, you can give Google's Wear OS platform a try with Fossil's $275 Q Control touchscreen smartwatch. It lacks GPS and support for NFC payments, which is why the Gear Sport is a better fitness-focused smartwatch for Android users, but Fossil's Google Assistant integration and stylish design make it a solid contender. However, smartwatches with Qualcomm's new Snapdragon Wear 3100 processor start shipping in October, so you may want to hold off until we put them to the test.