On Tuesday, Whatsapp announced that it’s implementing end-to-end encryption, an upgrade to its privacy protections that makes it nearly impossible for anyone to read users’ messages—even the company itself. Whatsapp will integrate the open-source software Textsecure, created by privacy-focused non-profit Open Whisper Systems, which scrambles messages with a cryptographic key that only the user can access and never leaves his or her device. The result is practically uncrackable encryption for hundreds of millions of phones and tablets that have Whatsapp installed—by some measures the world’s largest-ever implementation of this standard of encryption in a messaging service.
This is believed to be the largest deployment of end-to-end encryption ever.
In its initial phase, though, Whatsapp’s messaging encryption is limited to Android, and doesn’t yet apply to group messages, photos or video messages. Moxie Marlinspike, Open Whisper System’s creator and a well known software developer in the cryptography community, said that Whatsapp plans to expand its Textsecure rollout into those other features and other platforms, including Apple’s iOS, soon.
You can read the details in the announcement on Whisper Systems’ blog at https://whispersystems.org/blog/whatsapp.