What devices does Cardiogram work with?

Supported phones:

Apple iPhones
Android devices with Google Play Store

Supported wearables:

All Apple Watch models.* The Cardiogram companion app for the Apple Watch requires WatchOS 6 and above.
All Wear OS by Google wearables - Fossil, Mobvoi, Misfit, etc.
The Samsung Galaxy Watch 4 (released in 2021), the Cardiogram companion app, is required on the watch for Cardiogram to work properly.
All Garmin wearables with a heart rate sensor - Fenix 5 Series, Forerunner, Vivoactive 3, etc.
All Fitbit wearables with a heart rate sensor - Fitbit Charge™, Fitbit Versa™, Fitbit Inspire HR™, Fitbit Ionic, Fitbit Alta HR, etc.

ECG Importing:

Only available with Apple Watch 4 and newer.

Workout Importing:

Apple Watch
WearOS Watches
Fitbit

Devices not currently supported:

We currently do not support any HR straps like Polar or Garmin, Samsung watches from before 2020, Amazfit, Mi Band, Withings, or other smartwatches that do not run on WearOS.