WhatsApp has enhanced its security encryption to protect messages sent from Android devices running the firm's app, aiming to protect over 600 million users from organisations snooping on their communications.
The Facebook-owned company is using TextSecure open-source code from secure messaging firm Open Whisper Systems to add end-to-end encryption for WhatsApp on Android devices.
The move means that even WhatsApp will not be able to decrypt its users' messages, making the conversations as private as possible.
Around 600 million people stand to benefit from the improved security features, as the data scrambling system makes it much more difficult for messages to be intercepted.
Most encryption systems scramble messages only when they are in transit between a device and the server that routes them to a recipient, but TextSecure maintains the encryption for the duration of the message's journey from one device to another.
A blog post on the Open Whisper Systems website said that the company will roll out the new security features to other mobile operating systems, which is likely to include iOS.
"The WhatsApp Android client does not yet support encrypted messaging for group chat or media messages, but we'll be rolling out support for those next, in addition to support for more client platforms," the firm said.
"We'll also be surfacing options for key verification in clients as the protocol integrations are completed."
Open Whisper Systems explained that it has been working with WhatsApp for the past six months, during which time it learned how to scale its encryption service for many millions of users.
The security firm claimed that its work with WhatsApp represents the largest deployment of end-to-end encrypted communications in history.
Making WhatsApp attractive by offering robust privacy features is likely to be a key concern for Facebook, which will want to maximise the impact of its $22bn acquisition of WhatsApp.
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