The calls use VOIP, or voice online, indicating they go over the Internet by means of a WiFi connection or the customer's cellular data plan.
Oku na-eji VOIP, ma ọ bụ olu na Intanet, nke pụtara na ha na-aga n'Intanet site na njikọ WiFi ma ọ bụ atụmatụ data mkpanaka onye ọrụ.