Chatfuel - Chatfuel is the best bot platform for creating an AI chatbot on Facebook.
Dialogflow - Conversational UX Platform. (ex API.ai)
ChatBot - Easy to use chatbot platform for business
Octane AI - Octane AI offers tools to create a bot and engage customers and audience via messaging.
Landbot - An intuitive no-code conversational apps builder that combines the benefits of conversational interface with rich UI elements.
Recast.AI - Recast.AI is the leading platform to build, connect and monitor bots.