Amazfit Helio Strap

Amazfit Helio Strap is an armband from 2025, sitting in the budget band at an indicative $99.

It reads 16 of the 33 signals this comparison tracks. Nothing at all from body composition.

By sensor class: 10 at consumer grade. That grade is my classification of the hardware, not a lab test. Those readings come from an optical heart rate sensor, an optical blood oxygen sensor, a skin temperature sensor and an accelerometer. Blood oxygen is measured through the night, not continuously through the day.

Its 10 days per charge are the 4th longest of the 11 devices of its kind here that publish a figure. Rated 5ATM, fine for swimming. It weighs 20 g. No subscription is required.

Screen-free, subscription-free optical HR band (wrist/upper-arm); BioCharge readiness, VO2max; no GPS/ECG.