Person uses smart watch to pay for something wirelessly

The smart watch features you actually need

Published 23rd December 2022
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With all the jargon surrounding smart watches, it can be difficult to know which features you actually need. OnBuy is here to break down the different features you can commonly find in the leading brands and why you should pay attention to them.

Health monitoring

Health monitoring is one of the most useful features built into modern smart watches. This is a catch-all term for a series of sensors that give information about your health and wellbeing.

These sensors can be super sophisticated. One example is an optical sensor that detects your pulse by bouncing a green light off your skin and measuring how much of the light is absorbed by your blood. If you like to keep track of your workouts, be sure to look out for a watch with one of these.

Monitoring your heart rate helps you make sure you are exercising hard enough and recovering well enough after a bout of high-intensity exercise. This is just one of the ways in which a smart watch can help to improve your health. Popular options include the Apple Watch 7, the Fitbit Versa 3 and the Huawei Watch Fit.

Another health monitoring feature you'll want to look out for is sleep monitoring. When you're asleep the watch measures your pulse and combines the data with readings from from an accelerometer (a device that measures movement speed). It can then calculate not only how many hours you've slept, but the quality of  your sleep, too. Stress monitoring is another useful score that's derived from the pulse monitor, giving you gentle reminders to relax.

Paying with a smart watch

If you’re on the go a lot, you may appreciate a smart watch’s ability to act as a payment method. With just one tap, you can pay for your morning coffee, new pair of shoes or train tickets.

Many of the leading smart watch brands have created their own mobile payment system, all of which are facilitated using Near Field Communication (NFC), the same technology used for Contactless payments on debit and credit cards. Look through the specification of the smart watch you'd like to buy for NFC payments to know if you can pay for lunch with a wave of your wrist.

One thing to be aware of is that the company that makes your new smart watch must have a contract with your bank's payment processor, which may change from region to region. For example, Samsung smart watches are compatible with Visa, Mastercard and American Express, meaning you can almost certainly connect your card and make payments. Xiaomi smart watches, on the other hand, only work with Mastercard cards, and even then only in some nations.

Is this an essential feature for men's and women's smartwatches? That depends. If you're a casual user who never leaves their purse or wallet behind, possibly not. But this feature is incredibly useful if you're going clubbing or to a party and you don't want to carry your physical card with you.

Smart watches for calls and texts

One of the most popular smart watch features worth considering is call and text support. This can be incredibly useful but not every model can make calls or send messages.

For example, exercise-focused fitness and activity trackers may offer just text and call notifications, but not the ability to answer a call or reply to a message on the watch itself. But smart watches with large face plates usually allow users to respond to messages and answer calls on the watch face.

Some top of the range smart watches will even let you make calls if your phone is miles away! These gadgets have an e-SIM and an LTE inside their frames, which turns them into a kind of mini-phone. You can take calls and send messages when your phone is unavailable - you can even stream songs or download photos with mobile data.

If this sounds like a must-have feature, make sure you buy the LTE version of the smart watch, as brands charge more for models that include an LTE aerial. You'll also need to check with your phone's network provider to know if your watch can piggy-back off your phone's data plan.

Waterproof smart watches

These days most smart watches claim to be waterproof. The benefits of this are obvious: one of the perils of wearing an expensive piece of tech on your wrist is it dying after you forget to take it off before showering. And with swimming being such a popular way to keep fit, you'll need water resistance to track your progress in the pool. However, not all waterproof smart watches are equally waterproof.

For smart watches, the most common water resistance measurement is the ATM system. This measures how much pressure your watch can stand before breaking. This is important for water resistance because the deeper in water you get, the more pressure an object is put under.

It's not just depth, but also force of movement that determines how much pressure the watch feels: When you're swimming quickly through shallow water, you can put the watch under the pressure equivalent of a dive without realising it.

Most smart watches have a 3 ATM water resistant rating at least. This means they'll survive the equivalent pressure of 30 metres under water. This will protect against the rain and other water splashes, and you'll be able to take your watch into the shower, but 3 ATM isn't enough for swimming.

For that you'll need a water resistance rating of at least 5 ATM. Some waterproof smart watches from fitness brands like Garmin have a 10 ATM water resistance, allowing you to put these under the stress of 100 metres of water. Such smart watches are suitable for snorkelling or swimming relatively short depths underwater.

At time of writing there is not a smart watch suitable for scuba and saturation diving. If you're looking for a watch to take with you on an undersea exploration, we recommend buying a diving watch.

Smart phone operating systems

As a piece of smart tech, every smart watch has an operating system (OS) that controls its features and functions. Like a desktop PC, which OS your watch uses determines which apps it can run as well as its compatibility with different smartphones.

Most manufacturers have created their own OS for their watch. Apple Watches use the watchOS, which is heavily integrated with the iOS system used for iPhones and iPads. It's not compatible with phones running Android. To buy Android smart watches you'll have to look at different brands, like watches running Google's own WearOS, as well as Samsung's Tizen, Huawei's HarmonyOS and others.

In conclusion, smart watches come with many brilliant features, but which ones are essential depends on what's important to you and how you'll use your new watch. If you want more help finding the perfect smart watch for you, read our smart watch buying guide.

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