Necklace turns real-time UV exposure into personalized sun care guidance

A necklace that can track personal sun exposure has hit the wearable beauty market. The90 has launched Gem, which tracks real-time UVA and UVB exposure and translates the data into personalized guidance. The necklace, alongside its companion The90 app, is touted as “the first” personal sun intelligence system. The system combines live UV measurement with each user’s skin profile, sunscreen use, and protective clothing. The beauty tech brand says its Gem helps women move beyond generic UV estimates and make more informed decisions about sun exposure, sunscreen timing, and healthy skin aging.