Chalk up another victory for user privacy.
Add Viber to your list of secure messaging apps, along with Apple’s iMessage and Facebook’s (???) WhatsApp. The fact that FaceBook owns WhatsApp is a little disconcerting since FaceBook makes all its money from reading all of your stuff and selling it to advertisers, but they have been improving with regards to governments requests.
But end-to-end encryption means that your messages cannot be read by the company providing the service, nor the government trying to spy on you, so these moves are designed to protect your constitutional right to privacy.