Popular instant messaging app WhatsApp, on Tuesday, announced that it is turning on end-to-end encryption for all its users by default. The company says that every call a user makes, every text message they send, all photos and videos they share will now be more secure. Furthermore, the encryption status of any chat is visible under the chat’s preferences screen. The announcement comes a little over a year after the Facebook-owned company partnered with Open Whisper Systems, a nonprofit software group that develops collaborative open source projects with a mission to “make private communication simple.” The end-to-end encryption feature is available on the latest version of the app.

WhatsApp has also made available the technical details about how the two companies implemented this feature (PDF).
https://www.whatsapp.com/security/WhatsApp-Security-Whitepaper.pdf

WhatsApp has enabled end-to-end encryption across all versions of its messaging and voice calling software, according to a Tuesday announcement on the company’s website.

Given that WhatsApp is already in use by over 1 billion people worldwide, as users upgrade to the latest version, it will become the most widely used end-to-end crypto tool.

“We live in a world where more of our data is digitized than ever before,” Jan Koum, a WhatsApp co-founder, wrote in a company blog post on Tuesday. “Every day we see stories about sensitive records being improperly accessed or stolen. And if nothing is done, more of people’s digital information and communication will be vulnerable to attack in the years to come. Fortunately, end-to-end encryption protects us from these vulnerabilities.”

Forget Apple vs. the FBI: WhatsApp Just Switched on Encryption for a Billion People
http://www.wired.com/2016/04/forget-apple-vs-fbi-whatsapp-just-switched-encryption-billion-people/