Wit.ai - Easily create text or voice based bots that humans can chat with on their preferred messaging...
Gomix - The easiest way to build the app or bot of your dreams
Botsify - Ever wonder if you could replace your live chat support system with a chatbot?. Its possible now with Botsify Chatbot For Website.
Chatfuel - Chatfuel is the best bot platform for creating an AI chatbot on Facebook.
Dialogflow - Conversational UX Platform. (ex API.ai)
Meya.ai - Build, train and host sophisticated bots.