What is a smart ring?

Smart rings are relatively new to the tech space and started to appear on digits over ten years ago. “The miniaturisation of batteries and electronics has enabled accurate sensing and monitoring of health information in a small form factor, which has allowed smart rings to become a bigger player in the wearables space,” says John Mastrototaro, CEO of Movano Health, a startup that is launching the Evie Ring for women later in 2023.

He adds: “At the same time, consumers are more aware of their health than ever before. Preference for a device that is more comfortable to wear for long periods of time, which is discreet and able to blend in with your existing look, and doesn’t have distracting screens, has increased demand for smart rings.”

It was mainly tech startups that made the move into smart rings, including features like letting us pay for items in shops or paying for travel without reaching into a wallet or purse. Now they’ve evolved to help us closely monitor our health, exercise and general wellbeing.

“It may seem counterintuitive, but the finger is a great place to track heart rate and sleep, so the likes of Oura have been able to offer powerful health features and accurate data,” explains Stables. “While smart rings are now established, Oura Ring is still the main player, but there are plenty of alternatives coming, which will start to land at the end of 2023.”

“Smart rings have the potential to make healthcare more accessible, enabling early intervention and better monitoring,” says Mastrototaro. “An affordable device that can be comfortably worn consistently, smart rings can help make healthcare more equitable and accessible to all, putting health information directly into people’s hands.”

He adds: “With this accurate health information at your fingertips, telehealth [devices that allow you to monitor your health yourself, at home] and remote monitoring can help manage chronic conditions and detect health issues earlier, resulting in lower costs for both patients and our country as a whole.”

Not all smart rings are built the same, but at their core they rely on similar hardware to deliver core ring features. These include motion sensors, like an accelerometer and gyroscopes, to track your daily steps or detect when you’re asleep.

There’s also optical-based biometric sensors that use light to penetrate the skin and detect changes in biometrics, like heart rate and temperature. There’s also room for batteries to make sure you can use the rings for days before they need to be charged again.

Some rings, which include biometric sensors to track things like heart rate and blood oxygen, will need to be worn on particular fingers to ensure they can deliver the most accurate and reliable data.

You’ll have more flexibility with wearing options with rings that don’t include these types of sensors. Like buying any ring, you’ll need to identify the correct size for you, and many companies will send a sizing kit first to make sure you get the best fit from the real thing.

Smart rings don’t have screens, so that places a big reliance on using your phone and a companion app you’ll need to download, to take a closer look at the data the ring monitors and also to adjust any of the ring settings.

The connection between phone and ring is done wirelessly, and while you don’t need your phone nearby at all times to use the ring, you will need to bring the two closer together when you want to transfer over your latest data via that companion app.

Smart rings can track a surprising amount and depending on which one you go for, they can match a lot of the metrics that a Fitbit fitness tracker or an Apple Watch can promise to track.

Right now there are smart rings that can count daily steps for those who like to have a better idea of how active they’ve been during the day. At night, some will monitor your sleep, capturing information like the time you’ve fallen asleep, and how long you’ve slept, and will break down your sleep time into sleep stages.

This information can be useful, simply to understand whether you’re getting enough sleep and helping you to better understand whether things you’ve done in the day – be it exercise or having a quick drink – can impact on sleep quality.

More advanced rings are capable of monitoring your heart rate throughout the day and night, which can offer insights, like resting heart rate and when your heart rate is unexpectedly high or low. Some can also use that heart rate sensor to measure heart rate variability, which is the measurement of intervals between heart beats, and can be an indicator of stress.

While not all measurements are designed to tell you if you have a serious health issue, they can prove useful for other reasons, as Chloe MacArthur, Senior Cardiac Nurse at the British Heart Foundation, explains:

“Wearable devices that detect heart rate can be helpful for improving exercise habits and eating behaviours, and they can provide motivation to lead a healthier lifestyle – all of which contribute to lowering the risk of heart disease. But they are not a replacement for medical advice, and they cannot provide a diagnosis.

“There is some evidence showing that they can help people spot the signs of common and often undetected irregular heart rhythm conditions, but much more research is needed to determine their accuracy,” MacArthur adds. “If a medical professional has advised you to keep track of your heart rate, talk to your doctor to make sure you choose a suitable device.”

It’s a similar story for a ring that can track temperature and blood oxygen levels. Oxygen is of course vital to all our bodily functions, and oxygen levels can be impacted by things like infections or respiratory viruses. Again, this data could be a potential indicator that you could be becoming unwell or not feeling 100%.

Away from monitoring things like fitness and general wellbeing, you can own smart rings that aim to make it easier to pay for things using existing technology already found in other items. So they can let you make purchases without scrambling around for a card or some change.

More will come in the future as well. “Companies such as Movano are already trialling blood pressure tracking from smart rings, so like other wearables, there will be medical-grade data delivered from our fingers,” Stables says.

How long you can use a smart ring before it needs charging again entirely depends on what the smart ring can track and how regularly it tries to track those things. Some rings can last around a week, while some rings don’t require any charging at all and will work forever.

Smart rings have to make room for batteries as well and with less room to play, but many already match the battery life you’ll enjoy on a fitness tracker or smartwatch.

If you have a smart ring that promises to track your heart rate or temperature all day and night, then that’s going to have a bigger drain on the battery. Closely monitoring your wellbeing through sensors demands more power.

No two rings are generally charged up the same way, and require their own dedicated charging setups, which you’ll need to plug into a mains or USB socket in your plugs or computer, and you’ll only be able to use that charger to power them up again.

Generally, rings can take anywhere from 20-30 minutes up to a couple of hours to charge, but it depends on how much charge they still have or whether they’re completely dead.

• Sleek form factor and design
• Frees up your wrist to wear something else
• Easy to sleep with and wear all day
• Can track a lot of what fitness tracker bands are capable of

• No screen, so need to look at your phone to check your data
• Limited features when it comes to accurately tracking exercise
• Some may require additional cost through subscriptions
• May need to use a sizing kit to get the best fit

While smart rings are still relatively small in number when compared to the number of fitness trackers and smartwatches that are available, there are some standout ones that offer a mix of features and design.

The most popular is the Oura Ring, which has been seen on the hands of the likes of Prince Harry and Gwenyth Paltrow. The latest Oura Ring Generation 3 starts at roughly £300 (from $299 on its official website), with the addition of a membership needed to unlock all of its features, costing an additional £5.99 a month. 

It comes in two distinct styles and in up to five finishes and has the ability to track steps, and monitor sleep, heart rate and blood oxygen levels. It then uses that information to better inform you if you’re ready to take on a busy day or you should consider taking it easy.

It’s the ideal smart ring for someone who wants to pay a little closer attention to their general wellbeing and also wants a smart ring that feels and looks like a traditional ring.

Something that the Oura Ring lacks that a ring like the RingPay made by Mclear offers, is the ability to make payments.

This is the only feature the RingPay offers, using the same technology used in contactless cards to let you raise your wrist at a terminal to pay for your shopping.

It costs £89.99, so is cheaper than an Oura Ring, it never has to be charged and you can also set it up to make sure it tops up the ring to make sure you always have some available money on it to spend. It also never needs charging.

Spend £10 more and you’ll get the second generation smart ring, the RingPay 2, which is thinner and lighter than its predecessor while offering the same functionality.

Circular Ring (£239) by French firm Circular is a smart ring that’s similar to the Oura and comes in different finishes using optical sensors that can track heart rate, breathing rate, temperature, blood oxygen and sleep.

Unlike the Oura, access to Circular’s features are all free through the companion app.

The Evie Ring by startup Movano launches in September 2023, and is a smart ring designed for women using sensors to track daily steps, heart rate, and sleep, and offering actionable insights based on that data.

For the more adventurous and sporty types who like the idea of wearing something that can take control of your smartphone while it’s packed away in a rucksack, there’s ArcX’s Smart Ring. 

The £49.99 smart ring connects wirelessly to your phone using Bluetooth and can then control features like changing music and accept incoming calls, and there’s an additional SOS feature so you can press it to raise the alarm in an emergency.