WiFi Calling: Making mobile phone calls over WiFi in locations with no phone reception:
Telstra brings WiFi calling to iPhones (The Canberra Times – 10/5/2017) (Applies to some other phones as well)
Telstra has introduced the ability to make and receive telephone calls (but not text messages) by utilizing your WiFi internet connection in locations with poor or no mobile phone reception.
This only works for Telstra mobile phone customers with a compatible mobile phone. Not all make/model phones are supported. This works like a normal telephone call – no extra apps are required.
Telstra has a document with instructions and a list of compatible mobile phones on this page.
Early reports suggest that this service may even work acceptably on nbn SkyMuster satellite internet services. This could prove to be a cheap alternative to an expensive mobile phone repeater.
Optus also has a similar service, however it requires a special app. Click here for more details.