What Smart UV-Tracking Necklaces Do
A smart UV-tracking necklace is a wearable pendant that continuously measures UVA and UVB radiation around the wearer, sending real-time UV exposure data to a companion app that turns those readings into personalized sun protection guidance and skincare recommendations based on the user’s unique skin profile, daily habits, and product use. The Gem, created by Stacy Salvi’s company The90, is a round pendant designed to look like jewellery while quietly monitoring sun exposure throughout the day. Sensors inside the titanium case capture UV levels as people move between indoors and outdoors, including time spent near bright windows or in a car. By logging cumulative exposure rather than single snapshots, the device builds a daily UV history that helps bridge the gap between generic SPF rules and the specific conditions someone’s skin faces.
Inside The Gem: Real-Time UVA and UVB Monitoring
The Gem focuses on turning invisible rays into clear, real-time UV exposure insights. Its internal sensor tracks both UVA, linked to long-term skin ageing, and UVB, more associated with sunburn, giving a split view of how different wavelengths hit the skin. According to The90, the pendant measures UV levels in many situations, from quick walks to outdoor workouts to sitting near sunny windows. Data is sent to a mobile app that displays live exposure graphs, cumulative daily doses, and time spent unprotected. The app also includes a burn timer that estimates how long someone can stay outside before their skin is likely to burn, based on their inputted skin type and sunscreen use. The Gem’s splash-proof design, nickel-sized footprint and battery life of up to a week per charge aim to make UV tracking a constant background function rather than another device to manage.
From Generic SPF Rules to Personalized Skincare Guidance
Where traditional sun advice is built around broad SPF guidelines, this UV tracking wearable tries to personalise protection. Users enter their skin type, sun habits, clothing preferences and sunscreen details, including SPF value and how much product they applied. The companion app then blends this personal profile with measured UVA and UVB exposure to build a tailored skin safety plan. It sets individual UV thresholds, sends reminders to reapply sunscreen, and suggests safer times to be outdoors based on real-time UV exposure. The app also separates daily UVA and UVB totals to link short-term burn risk with longer-term skin-ageing concerns. In practical terms, that means two people standing in the same sun can receive different alerts, reflecting differences in skin sensitivity, protection level and time already spent outside, replacing guesswork with specific, data-driven guidance.
Design, Pricing and The Fitbit Connection
The Gem stands out among smart necklace sun protection devices by aiming to look like jewellery first and a sensor second. Available in gold and silver finishes and roughly the diameter of a US nickel, it is designed to blend into everyday outfits rather than resemble a fitness tracker clip or patch. According to reporting on The90, The Gem has an introductory price of USD 199 (approx. RM930) and is planned to retail at USD 299 (approx. RM1,395) later. That positioning reflects its pitch as both fashion accessory and health device. The credibility behind the product is tied to its founder: Stacy Salvi spent eight years at Fitbit, including during its acquisition by Google, bringing experience from mainstream fitness trackers into this more specialised UV-monitoring space. Her move signals that sun exposure is being treated with the same seriousness as steps, sleep and heart rate.
Preventative Health Wearables Move Beyond Fitness
The Gem’s launch highlights a broader shift in wearables from tracking performance to preventing problems. Instead of counting steps or logging workouts, this smart necklace sun protection device focuses on the daily, cumulative UV exposure that quietly contributes to skin damage. The90 positions The Gem as a new category, even though earlier UV sensors have appeared as clips, wrist devices and patches. What feels new is the blend of fashion-first design, continuous real-time UV exposure data and personalised skincare guidance delivered in an app. As awareness of UV-related risks grows, this kind of preventative health wearable points toward a future where people monitor environmental factors around their bodies as closely as internal metrics. If step counters helped normalise fitness tracking, UV necklaces like The Gem could do the same for everyday sun safety.
