Dialogflow - Conversational UX Platform. (ex API.ai)
Whelp - AI-based Omni channel customer support platform with chat bot system (On premise and cloud based)
Octane AI - Octane AI offers tools to create a bot and engage customers and audience via messaging.
B2Chat - Instant messaging software to unify all of your chats in one single inbox.
Botkit - Botkit is an open source developer tool for building chat bots, apps and custom integrations for major messaging platforms.
SleekFlow.io - Sell, convert & support better on chat