Notebookcheck Logo

Luna Smart Ring 2.0 debuts as wearable with dedicated LifeOS AI and long battery life

The Luna 2.0 Smart Ring. (Image source: Luna)
The Luna 2.0 Smart Ring. (Image source: Luna)
With a battery life estimated at 21 days or more per charge, Luna claims to have launched one of the world's longest-lasting smart rings at IFA 2025. The second-generation wearable is also touted to have one of the best-trained AIs out there, particularly in terms of sleep-tracking and stress detection. The Luna 2.0 ring is also subscription-free and integrates its own chatbot.

Luna's latest smart ring comes with its own dedicated LifeOS, touted to "decode" the ways in which the user's physical and perhaps even mental health is affected by the world around it by tracking numerous vital signs over time.

They include a skin temperature sensor in addition to those for blood oxygen, heart rate and pulse oximetry. They are backed to help LifeOS 'learn' the wearer's "circadian alignment" (or 'body clock') over time to generate more and more personalized health and fitness insights via its own AI voice coach.

The 2.0 ring is also touted to deliver in-depth sleep-tracking, with metrics such as sleep latency, sleep efficiency, sleep cycles, respiratory performance and circadian rhythm alignment in general.

The wearable is also rated for predictive and individualized fertility tracking, as part of its "comprehensive activity logging" features.

Unlike some of its competitors such as those from Ultrahuman and Oura, it does not require a subscription. Luna claims that the data it collects is stored "securely" (although the brand does not say where exactly) and is never shared without the user's "explicit consent, in accordance with global data protection standards".

The new ring is made of PVD-coated titanium for 5ATM water resistance and comes in rose or yellow gold colors as well as silver and Midnight or Lunar black. Its weight starts at 3.5 grams (g), though, compared to 2.5g in the Ultrahuman Ring Air.

The Luna 2.0 is rated for as much as 30 days of battery life - so long as it is bought along with a ring box-like charging case.

That Surge Charger bundle is priced at $349/£329, as opposed to $300/£300 for the Luna 2.0 with a less portable dock charger.

The latest Luna Ring is available worldwide from now via its own website, while the Ultrahuman Ring Air is currently listed on Amazon at $349.

The new Luna Ring in its Surge Charger. (Source: Luna)
The new Luna Ring in its Surge Charger. (Source: Luna)

Source(s)

static version load dynamic
Loading Comments
Comment on this article
Please share our article, every link counts!
Mail Logo
> Expert Reviews and News on Laptops, Smartphones and Tech Innovations > News > News Archive > Newsarchive 2025 09 > Luna Smart Ring 2.0 debuts as wearable with dedicated LifeOS AI and long battery life
Deirdre O'Donnell, 2025-09- 5 (Update: 2025-09- 5)