Dialogflow - Conversational UX Platform. (ex API.ai)
Gomix - The easiest way to build the app or bot of your dreams
Messenger Platform - Discovery, chat extensions, and richer experiences
Recast.AI - Recast.AI is the leading platform to build, connect and monitor bots.
Api.ai - Api.
Chatfuel - Chatfuel is the best bot platform for creating an AI chatbot on Facebook.