Aivo - Skyrocket your Customer Service and Sales KPIs with a Chatbot powered by Artificial Intelligence. Give time back to people.
Dialogflow - Conversational UX Platform. (ex API.ai)
Zendesk Answer Bot - Chatbots
Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.
Tars - TARS enables users to create chatbots that replaces regular old webforms.
Botpress - Open-source platform for developers to build high-quality digital assistants