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Here are descriptions of the more relevant changes in

End-to-end security for messages

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Brand
brand client

 provide end-to-end security model, that was available only for secure calls: secure messages are now fully for voice calls when using ZRTP key agreement protocol. This version adds end-to-end encryptedsecurity model to secure messages.

Brand
brand client

changes

This version carries a User Interface redesign of clients and server, plus many new devices and OS version support.

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