WhatsApp - WhatsApp Messenger: More than 1 billion people in over 180 countries use WhatsApp to stay in touch with friends and family, anytime and anywhere.
Gajim - Full featured and easy to use Jabber client
Green Messenger - WhatsApp Messenger Web for Chrome. Text/Chat on computer. Notifications, messages, tools.
CoyIM - CoyIM is a safe and secure chat client.
App for WhatsApp by coldX - Integrated WhatsApp functionality on the Desktop.
Empathy - Apps/Empathy - GNOME Wiki!