Viber – allows you to chat with users of the software by making calls and writing text messages through the internet. The software conducts the synchronization of a phone book and automatically detects contacts where this software is installed. Viber enables to make calls to mobile and landline phones at low rates. The software allows users to send stickers, photos, voice or video messages and download games. Viber enables to join the popular chats to view information about celebrities or friends.