What is a smart ring?

It may be easy to view a smart ring as simply an item of tech-laden jewellery. But the underlying fact is that it could save your life.

With ever-evolving technology, smart rings are discreet wearables that have a range of lifestyle and health facets that can help make our everyday existence, easier, more efficient, and potentially healthier.

From monitoring simple distance travelled in terms of steps, they can increasingly be used in the same way as smartphones and smartwatches to offer travel passes, make digital payments, or monitor communication.

Yet where they are truly beginning to have an impact is as remote monitoring wearables for patients with chronic health conditions.

Real-time data

Easy to use, they have the technology to gather continuous, real-time, data on various body indicators such as heart rate, blood oxygen levels (SpO2), blood pressure, glucose levels, and body temperature, that can be transmitted to, or even alert, a physician.

Most brands offer a finger-size measuring facility before purchase to ensure a good fit, and facilitate the most accurate monitoring. These are important (https://www.techradar.com/uk/news/smart-rings) as smart rings are designed for 24-7 use.

Sky Labs’ CART-I, for example, is made of surgical steel, weighs around 4 grams, is dustproof and waterproof and can last up to 48 hours per charge. (https://www.smartringnews.com/smart-ring-products/cart-i)

It is almost a decade since the English firm McLear released the first smart ring in 2013, and although they are still not yet as widely used as smart watches, smart bands and earbuds, some analysts (https://www.smartringnews.com/posts/what-are-smart-rings-how-do-they-work) believe they are the future of wearable technology.

Mobile components

Smart rings can be linked to smartphones or computers and are loaded with mobile components, such as sensors for tracking, a Bluetooth chip (to sync data collected to a smartphone app), and NFC (near-field communication) chips for applications such as a travel pass or public transport ticket on tap-to-pay card reader terminals at transit gates, e.g. K Ring for Transport for London services (https://mykring.com/tfl).

The most common applications are still in products for the health and fitness category to record daily activities and calories burned, but some also have a component monitoring sleep pattern.

Most smart rings allow control of smartphones and other devices, helping reduce screen time, but as they do not have a screen, they use less battery power than smart watches.

Tracking Atrial Fibrillation

More advanced models, however, are having particular and relevant applications for the medical field.

The CART-I ring, for example, is a cardio tracker able to detect atrial fibrillation (AF), a condition where the heart beats in an irregular way.

As the world’s first ring-type smart wearable heart rhythm monitoring medical device, it provides photoplethysmography (PPG) signals to measure heart rate from screening the bloodstream 24/7 through the user’s finger to measure irregular pulse waves. It then transmits the data to a cloud platform where AI technology detects and analyses AF.

It also uses electrocardiogram signals to provide additional information to the user’s doctor, often without user intervention.

Authorised for use by the South Korean Ministry of Food and Drug Safety and certified by the European Union, it was officially launched in the UK – the sixth largest medical device market in the world – late last year. (

https://www.mobihealthnews.com/news/asia/sky-labs-develop-more-health-monitoring-wearables-latest-funds) (https://pulsenews.co.kr/view.php?year=2021&no=1046676)

Ongoing research

AF is the most common type of irregular heartbeat, affecting about 1% of the population, with 4.5 million confirmed cases in the EU and 2.3 million in the United States, with that expected to rise significantly by 2050. AF also leads to increased stroke risk. 

But it is difficult to detect because it can be intermittent, hence the need for long-term continuous monitoring through a device such as a smart ring, which is often more discreet and less cumbersome as a monitoring tool for patients. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7246533/). Research has examined the value of AF detection methods and their value in extending event observation time.

Meanwhile, a study, led by cardiologist and arrhythmia specialist Timothy Betts, professor of medicine at Oxford University, is evaluating the effectiveness of alerting AF patients to take anticoagulants when needed, with Sky Labs providing one of the wearable devices for the clinical trial (https://www.businesswire.com/news/home/20210222005010/en/Sky-Labs-CART-I-Invited-to-a-Clinical-Study-of-Oxford-University-Professor-Betts).