Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.
Drift - A messaging app that helps you grow your business.
Talkus - Chat with your website users from Slack
Zopim - Live chat is a faster and more personal way for you to engage your customers. Free for 14 days. No credit card required.
HeyHi.sg - Video call with interactive whiteboard
GetChat.App - Add WhatsApp chat to your website for free