Pull the lower eyelid down gently so the pink inner lining is visible, then hold the phone about 15 cm away in even light.
Fill the outline with the pink inner lining of the lower eyelid. Keep the phone steady; avoid flash and coloured lighting.
Evidence
Every figure on this page is produced by the frozen evaluation run in this repository. Nothing here is illustrative.
Results will be published here once the validation sweep selects a model and the frozen test run completes.
Method & limits
How it works
The camera photographs the conjunctiva, the pink lining inside the lower eyelid, which carries the same capillary blood as a finger-prick. A regression model estimates haemoglobin in g/dL from that image. All computation happens on your device.
What it cannot do
This is a screening aid, not a diagnosis. It cannot confirm anaemia, cannot rule it out, and cannot replace a laboratory blood test. A result outside the normal range is a reason to seek a blood test, not a reason to start treatment.
Do not use it in an emergency or to make a treatment decision.
Fairness
Performance is reported separately by skin tone (ITA°) and by imaging site. Where the model is not equally reliable, that gap is stated rather than averaged away.
About
No photograph leaves this device. The app makes no network request with image data.