From Viber Media:
Viber for Mac lets you send free messages and make free calls to other Viber users, on any device and network, in any country!
Viber syncs your contacts, messages and call history with your mobile device, so you can start the conversation on the Viber mobile application and continue from the comfort of your Mac.
- Best-quality HD voice calls
- Video calls
- Free text and photo messages
- Group conversations
- No registration, passwords or invitations required
- Contacts and messages sync between your mobile and Mac
- Transfer ongoing calls between devices