Good news to all of you who work in big office buildings or remote locations that happen to have good connectivity but bad cell service.
We have all used Wifi – Voice over IP services like Skype, but today AT&T has turned on the service that allows you to make the same type of calls via your regular dialing interface when your cellphone has a good Wifi connection, but a poor cellular connection (a common occurrence in large office buildings).
To turn on Wi-fi calling:
Go to Settings
Find the correct setting using the new Setting search bar (at the top of the screen on iOS 9+)
simple enter “Wi-Fi” and you will see an option called “Wi-Fi Calling”
Turn it on and agree to the terms.
It will also ask you to enter your preferred 911 address (so that they can route emergency services to your most likely address in the case of an emergency).