Hidde Chats. Viber follows Whatsapp to provide encryption.

Viber-Lanka

Now Whatsapp and Viber Apps offer their customers a way to do encryption on their messages. Even you can hide your chats and discretely delete messages from your contacts. This is very important to some of the users to keep their messages from other people from viewing them.

Facebook owned Whatsapp introduced this facility last week and this week Viber followed suit and provided this facility to its members through its Apps. To get the benefit of this service simply update the App with the latest codes in their devices (Smartphone and Tablets) and to follow their instructions  So your App will provide complete privacy by encrypting all your communication.

Read here what Viber says about their new development.
Here https://support.viber.com/customer/portal/articles/2017401-viber-security-faq#.Vxd_d0-deSo

Latest. Here is one important Tweet from Whatsapp.
WhatsApp Inc. ‏@WhatsApp 25 Feb 2015
WhatsApp Web: https://web.whatsapp.com – Firefox and Opera browsers are now supported!
Send and receive Whatsapp messages right from your computer.
Read the Tweet: https://twitter.com/whatsapp?lang=en

whatsapp