A month of side-by-side testing found the Amazfit Cheetah 2 Ultra tracked closest to a Garmin Index BP Monitor, with readings typically within 2 to 4 mmHg for both systolic and diastolic pressure.
Three devices were tested on the same wrist at morning, midday and end-of-day intervals: Samsung Galaxy Watch Ultra, Amazfit Cheetah 2 Ultra and YHE BP Doctor Fit, with Garmin's arm-cuff monitor used as the reference.
Samsung's Galaxy Watch Ultra was usually 12 to 14 mmHg high on systolic and 10 mmHg low on diastolic readings, while the BP Doctor Fit often ran about 15 mmHg high on systolic and produced the most errors.
Both Samsung and Amazfit require monthly arm-cuff calibration, but Amazfit's blood-pressure feature is cleared only outside the US, where the writer enabled it by setting the account location to Brazil.
The comparison highlights growing demand for wearable hypertension tracking as high blood pressure affects about 1.3 billion people worldwide and many users want easier monitoring than a standard cuff.