Octane AI - Octane AI offers tools to create a bot and engage customers and audience via messaging.
BotList - An app store for bots
Dialogflow - Conversational UX Platform. (ex API.ai)
ManyChat - ManyChat lets you create a Facebook Messenger bot for marketing, sales and support.
Botkit - Botkit is an open source developer tool for building chat bots, apps and custom integrations for major messaging platforms.
Chatbot Templates - 50+ bot templates you can use in one click