Leep Health is a British wearable company focused on sleep tracking. Its Leep Smart Ring is a screenless titanium ring worn day and night. It tracks sleep, recovery, activity and several body signals, with app results and no required subscription.

How it works
Optical sensors shine light into the finger to estimate heart rate, heart rate variability and oxygen. A temperature sensor follows overnight changes, while motion sensors detect activity and periods of rest. Software combines these signals to estimate sleep timing and stages, movement and recovery trends. The ring can also use workout information from apps.

Key considerations
The ring must fit closely without rotating for reliable optical readings. Movement, cold hands, skin contact and missed charging can reduce data quality. Sleep stages and recovery values are algorithmic estimates.