WhatsApp: Free Messaging App with End-to-End Encryption

WhatsApp is a popular instant messaging app that allows users to send and receive text messages, voice notes, photos, videos, and documents over the internet. It was founded in 2009 by Brian Acton and Jan Koum, and acquired by Facebook in 2014. WhatsApp is available for free on both Android and iOS devices, and also offers a web version. The app uses end-to-end encryption to ensure that messages and calls are secure and private. It is used by over 2 billion people worldwide and is particularly popular in countries like India, Brazil, and Indonesia.