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.
GetChat.App - Add WhatsApp chat to your website for free
RELE.AI - RELE.AI is the first enterprise Virtual Bot Assistant, allowing you to document client conversations and interact with your CRM without ever leaving WhatsApp (desktop & mobile).
Avochato - Text messaging for your business.
BetterChat for WhatsApp - Gorgeous new full-featured WhatsApp client for the Mac.
Talkus - Chat with your website users from Slack