WhatsApp is a popular messaging app that is preferred over traditional text messages for a variety of reasons. It is a data-based instant messenger rather than a traditional SMS text messaging service, so messages are transferred much faster. Additionally it is cross-platform compatible, meaning that messages can be sent and received between iPhone, Android, Windows and Blackberry devices. It can also be used internationally, since it uses internet data rather than SMS networks, which can be costly while travelling. WhatsApp also offers end-to-end encryption, which provides an extra layer of security for messages and calls. Lastly, it offers a wide range of additional features and services, such as group chats, multimedia files sharing, and video and voice calls.