Round watch face versus square, fitness emphasis versus other smart features, iOS versus Android compatibility. Whether you're looking for your first or replacing an old one, there are a lot of factors to consider when buying the best smartwatch for your needs, especially because it's going to be strapped to your wrist almost 24/7 if you're planning on using it to track your sleep. We've rounded up five of the best smartwatch functions based on function, price and compatibility to help you decide which one is right for you.

The Apple Watch Series 5 may be the most expensive one on our list, but it's the gold standard when it comes to smartwatches. It has all the smartwatch features we loved about its predecessors, including the seamless compatibility with other Apple devices, advanced fitness tracking and potentially lifesaving health features like a built-in EKG heart rate monitoring and fall detection. The biggest downsides to the Apple Watch: It's iPhone-compatible only, and it has shorter battery life than most of its competitors. Read our Apple Watch Series 5 review.

It's been nearly three years since the Apple Watch Series 3 made its debut, but it continues to hold its own. This Apple smartwatch may not have the always-on display, EKG heart rate tracking or fall detection smartwatch functionality feature that the Series 5 has, but it has everything else for half the price. And with the update to WatchOS 7 coming in the fall, the Series 3 will also be adding sleep tracking to its long list of health and fitness features. One potential drawback of the Series 3 is that the older watch may stop getting updates before the Series 5 does. This year's WatchOS 7 update for example, left out the Series 2, Series 1 and original Apple Watches. Read our Apple Watch Series 3 review.

Angela Lang/CNET The Versa 2 is the best Fitbit you can buy if you're looking for an activity tracking fitness smartwatch that can do more than just track steps. With a battery that lasts longer per charge than those of most other wearables on this list, the Versa 2 also works with Android or iPhone smartphone and has Alexa on board. You don't get built-in GPS (unlike Fitbit's latest tracker, the Charge 4) so you will need to take your smartphone with you to track route and distance on runs. But the Versa 2's biggest strength is the Fitbit app, which presents your workout details clearly so you can easily interpret your efforts. Read our Fitbit Versa 2 review.

Angela Lang/CNET There's no question that the Galaxy Watch Active 2 is Samsung's sleekest smartwatch to date, with two sizes to fit more wrists. The combination of a touch bezel and touchscreen makes navigating the interface on this Android smartwatch a breeze and you can also get an LTE edition of this Samsung smartwatch so you can receive calls on the go, without needing your smartphone nearby. Battery life can be inconsistent, however, and the ECG isn't active outside of Korea just yet. Read our Samsung Galaxy Watch Active 2 review.

If you're looking to get more bang for your buck, you'll be hard-pressed to find a better deal than the Amazfit Bip S. This $70 smartwatch is compatible with both Android and iOS devices and checks most of the boxes when it comes to features: always-on display, built-in GPS tracking and the best battery life of any device on this list. You can get up to 40 days of use on a charge, or about two weeks of heavy usage with the GPS on and brightness up (a time that's still above and beyond the rest). You may have to make some sacrifices when it comes to aesthetics, though, as it has a plastic casing and the screen isn't as bright or responsive as the ones on the Galaxy and Apple Watch. Read more about the Amazfit Bip S.

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