WhatsApp Messenger 
is a freeware and cross-platform messaging and Voice over IP (VoIP) service owned by Facebook.[45] The application allows the sending of text messages and voice calls, as well as video calls, images and other media, documents, and user location.[46][47] The application runs from a mobile device but is also accessible from desktop computers; the service requires[48] consumer users to provide a standard cellular mobile number. Originally, users could only communicate with others individually or in groups of individual users, but in September 2017, WhatsApp announced a forthcoming business platform that will enable companies to provide customer service to users at scale.
Developer(s)
WhatsApp Inc.
Initial release
January 2009; 9 years ago
Stable release(s)
iOS 2.18.81 / August 5, 2018; 2 months ago
Android 2.18.300 / October 2, 2018; 16 days ago
Windows Phone 8, Windows 10 Mobile 2.18.52
Symbian 2.16.57
BlackBerry 2.17.2 / June 26, 2016; 2 years ago
Preview release(s)
Windows Phone 8, Windows 10
Written in
Erlang[8]
Operating system
Android, iOS, Windows Phone, BlackBerry OS, Symbian (there are Windows, macOS and web app clients that work only in presence of a connected mobile app client)
Type
Instant messaging and social media
License
Freeware
Alexa rank
Positive decrease 52 (As of 1 October 2018)[9]
Website
www.whatsapp.com
