WiFi calling lets you make and receive calls using your WiFi connection instead of the mobile network. It's like having your phone calls travel through your broadband rather than a phone mast.
Android 🤖
To set up WiFi calling on your Android device:
Open Settings → Network and Internet → Mobile Network → Advanced → Access Point Names
Tap + to add new APN
Set Name: Honest and APN: gamma (leave everything else blank)
Save and select the new "Honest" APN
Restart your phone
Open Phone app → Settings → WiFi Calling
Select your Honest SIM and enable WiFi Calling
iOS 🍎
To set up WiFi calling on your iPhone:
Open Settings → Mobile Data → Mobile Data Network
Check APN says gamma (change it if it says "three.co.uk")
Restart your phone
Go to Settings → Phone → WiFi Calling
Turn on WiFi Calling
What happens next? 🤔
Your phone is now set up for WiFi calling! You can make normal phone calls and send text messages at standard rates whenever you're connected to WiFi, even without mobile signal. This works anywhere in the UK where you have a WiFi connection.