A:Answer S8 and S8+ can make wifi calls. There is a pull down screen visible by swiping your finger down from the top of the display that has this setting. There are 3 possible settings, 1) Wi-Fi Preferred, 2) Cellular Network Preferred and 3) Never use cellular Network. You can select any one of these options. About Nigeria, I don't know, but I would assume there would be no problem
