ECG App not appearing on Apple Watch (Region: INDIA)
Make sure that you also update your iPhone to the latest version of iOS as well. The ECG feature is on the iPhone and it needs to be enabled there 1st.

Set up the ECG app


Open the Health app on your iPhone. 
Follow the onscreen steps. If you don't see a prompt to set up, tap Browse > Heart > Electrocardiograms (ECG) > Set Up ECG App. 
After you complete set up, open the ECG app to take an ECG. 




https://support.apple.com/en-us/HT208955