WhatsApp has made end-to-end encryption a default feature in the most recent update to its messaging app for Android.
The encryption fete is significant, as it makes WhatsApp one of the most secure text messaging apps available. With end-to-end encryption, any party other than the message sender and receiver cannot decrypt messages sent between WhatsApp users – this includes WhatsApp, meaning that any law enforcement requests for decryption are moot.
WhatsApp partnered with Open Whisper Systems for the encryption launch, using the company's open source TextSecure protocol. TextSecure's forward secrecy feature is known for its ability to keep messages encrypted even if a hacker cracks the key exchange between users.
Twitter acquired Open Whipser in 2011 for an undisclosed amount, but Whisper Systems' TextSecure software code was released as free and open source shortly after the acquisition.
In a blog post announcing the encryption partnership, Open Whisper expressed pride for the encryption accomplishment, noting that Android's fragmented device platforms pose ongoing challenges to ensuring the deployments run successfully. But it also gave a hat tip to WhatsApp for its contribution to the year-long project:
WhatsApp deserves enormous praise for devoting considerable time and effort to this project. Even though we're still at the beginning of the rollout, we believe this already represents the largest deployment of end-to-end encrypted communication in history. Brian Acton and the WhatsApp engineering team has been amazing to work with. Their devotion to the project as well as their thoroughness in getting this done are inspiring in a world where so many other companies are focused on surveillance instead of privacy.
For now, the encryption is for Android only, with no word yet on when it will hit iOS. Additionally, the WhatsApp Android client does not support encrypted messaging for group chat or media messages, but Open Whisper says it plans to roll out support for those next, as well as support for more client platforms.