App for WhatsApp by coldX - Integrated WhatsApp functionality on the Desktop.
UserVoice - UserVoice integrates easy-to-use feedback, helpdesk, and knowledge base management tools in one platform that empowers users to speak and companies to understand.
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.
Freshdesk - Freshdesk is a cloud-based customer support software that lets you support customers through traditional channels like phone and email, social channels like Facebook and Twitter, and your own branded community
WhatsGreen Multi Messenger - Easy access to WhatsApp, Line, Telegram, FB Messenger and many others via the Chrome toolbar.
Zendesk - Zendesk is a beautiful, lightweight help-desk solution.