Oura

Oura makes a smart ring that tracks health and fitness metrics from sensors on the finger, where signals like heart rate and body temperature can be measured more reliably than from the wrist. The ring records sleep stages and quality, resting heart rate, heart rate variability, respiratory rate, skin temperature trends, activity and steps, and menstrual cycle patterns, and the companion app distills this into three daily scores for Sleep, Activity, and Readiness plus longer-term trends and personalized guidance. Oura has expanded the app well beyond the original sleep focus, adding stress and resilience tracking, an AI advisor that answers questions about a member's data, illness-onset detection from subtle physiological changes, and metabolic features that combine meal logging with continuous glucose monitor data, as well as blood-biomarker testing through partner labs. The company has grown quickly, selling millions of rings and reaching a valuation around eleven billion dollars, and roughly half of its members use it to help manage a chronic condition. Oura is sold as a hardware purchase for the ring plus a paid monthly membership that unlocks the full set of scores, insights, and features; without the membership the app shows only limited data.