WiFi calling can allow users to make calls in areas with poor reception, letting you take calls and get messages where the cellular network might not reach and improve call quality. WiFi calling can also extend battery life as it is more power efficient than a standard call made directly over the network. With customers’ demand for always-on connectivity is increasing, mobile phone networks are turning to Wi-Fi calling to enable more functions. OnePlus has declared that its new flagship OnePlus 6 is already equipped with the necessary bands to support WiFi calling. But what is WiFi Calling, how to turn on WiFi Calling?
What is WiFi Calling?
Instead of using your traditional network connection, Wi-Fi Calling is a feature that allows you to make calls and send text messages via a Wi-Fi network. It means using a Wi-Fi connection you have set up at home, or whatever Wi-Fi hotspot you happen to be on when you’re out. In most instances, it’s like any other phone call, and you still use normal phone numbers.
In terms of specialty, with Wi-Fi Calling, cellular packets of a phone call is transferred over the internet from your OnePlus 6 to your carrier, taking advantage of higher data speeds than most cellular connections in the meantime, then convey through the cellular network and finally delivered to the intended recipient.
How to Enable OnePlus WiFi Calling?
Certain OnePlus 6 users in Germany have been complaining that WiFi calling is inexplicably disabled in the country. OnePlus has clarified the option to support VoLTE or WiFi calling is entirely up to the carriers. OnePlus has not disabled or removed any of these features from its latest model.
A OnePlus user shared his way to enable WiFi calling, below are the steps that may help you with your OnePlus 6 or other predecessors.
1. Long-press on an empty space on your home screen and select Widgets.
2. Select Activities and drop it onto your home screen.
3. When the Activities menu appears, scroll down until you see Settings and tap it to reveal more options.
4. Scroll down until you see Enhanced radio control and long-press it to make the menu appear. If you tap on it, it will just create the widget on your home screen and you will have to start back from step 1 to do the rest.
5. In the Enhanced radio control menu, tap on the option that says TURN ON WFC DEBUG. It should now say TURN OFF WFC DEBUG. WFC stands for wi-fi calling, in case you are wondering.
6. Press the back button to return to the Activities menu.
7. Scroll down some more until you now see the Wi-Fi calling option and long-press it to make the menu appear.
8. Once you are there, turn on the switch found right below the search icon, which looks like a magnifying glass.
9. An option called Calling preference will now appear. You have two options to choose from below, pick whichever you want:
Wi-Fi preferred: All calls are made over an available Wi-Fi network. If there are no available Wi-Fi networks, then calls are made over the cellular network.
Cellular preferred: All calls are made over the cellular network. If the cellular network is not available, then calls are made over an available Wi-Fi network.
10. Exit the Activities menu and simply reboot your device. You will now have the ability to make Wi-Fi calls.
Read More:
blog.easyacc.com 
this doesn’t work at step 2…
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