If you're wishing to disable your iPhone, Apple Watch, or connected app on your Apple Health account as an activity tracker you need to "un-allow" the Calorie Cloud app to read your "Step" and "Active Energy" data from Apple's Health App (Also known as HealthKit).
How to disable (this is assuming you have the most updated version of the app):
- Locate & open the "Health" app on your iOS device.
- From the main "Health Data" screen, tap on "Sources" at the bottom of the app.
- Tap on Calorie Cloud and Confirm that both "Active Energy" and "Steps" sliders are set to OFF (red).
The next step is to add another tracker. See here how to do that.