TL : DR -> Don't set raintalk as your default dialler. Only then will it start working, and you'll be able to make and receive calls with it, including via wifi connection. Tested on a Huawei P9 Lite, EMUI 5.0.4, Android 7.0.
Greetings
So I have a 6-year-old Huawei P9 Lite, running Android...
I live in an area where Rain's service is not good—sometimes almost none—during load shedding. I've got Vodacom as a backup. I use raintalk app for calling (while using Vodacom for data, but as soon as the Rain SIM card is removed, the app stops working. To cope with this problem, I've got to...