[…] Now in its third iteration, the Oura Ring tracks and analyzes a host of metrics, including your heart-rate variability (HRV), blood oxygen rate, body temperature, and sleep duration. It uses this data to give you three daily scores, tallying the quality of your sleep, activity, and “readiness.” It can also determine your chronotype (your Read more about The Oura Ring Is a $300 Sleep Tracker Suddenly needs a Subscription[…]