WhatsApp Messenger is a freeware, cross-platform messaging and Voice over IP (VoIP) service owned by Facebook. It allows the sending of text messages and voice calls, as well as video calls, images and other media, documents, and user location. The WhatsApp client application runs on mobile devices but is also accessible from desktop computers while the mobile device is connected to the Internet. The service requires users to provide a standard cellular mobile number. Originally, users could communicate only with others individually or in groups of individuals, but in September 2017, WhatsApp announced a forthcoming business platform to enable companies to provide customer service to users at scale.