Bro, its network based feature,helps in making call over Wifi....right now, it's not available in India..still in final testing phase..(if am not wrong)..jio and airtel is working on this..
Wi-Fi Calling is a service for Android and iOS smartphones providing the ability to make and receive phone calls over a Wi-Fi connection. It's simple to use with no separate application or log-in required. International rates still apply for international numbers.
