Cardiogram is a subscription billed through your phone’s play store account.
Like other apps with in-app subscriptions and purchases; If you delete the app or deactivate your Cardiogram profile, you are still responsible for unsubscribing to avoid being charged in the future.
Please follow these steps to ensure you are no longer subscribed.
iOS users: How to cancel a subscription from Apple.
Android Users: Cancel, pause, or change a subscription on Google Play.