Wellue is a health device brand offering oxygen monitors, electrocardiogram recorders and home monitors. Its O2Ring is worn around a finger overnight and is designed to track blood oxygen, pulse and movement overnight.

How it works

Red and infrared lights pass through the finger. Oxygenated and deoxygenated blood absorb the wavelengths differently, to estimate oxygen saturation and pulse. Motion adds context. The ring can vibrate when readings cross limits, while the ViHealth app displays graphs, oxygen drops, pulse and reports.

Key considerations

Cold hands, movement, poor circulation, nail products and a loose fit can distort readings. A vibration may encourage a position change, but it does not resolve the cause of low oxygen. Regulatory status varies across Wellue products and countries. The ring cannot diagnose sleep apnea, lung disease or an abnormal heart rhythm alone. Alarms also depend on charged hardware, thresholds and finger contact.