If you want to remove the app service, please follow these steps:
1. In order to cancel Premium subscription service see the question: “I purchased a new subscription service. How do I cancel the service and stop my payments?”
2. In order to cancel call and SMS route from the app to your device, before you uninstall the app, set the Block option for incoming calls on the “SET” tab.
3. To cancel the Whatsapp account, please see the instructions at the following link: https://faq.whatsapp.com/en/android/21119703/
4. Uninstall the application