Chatfuel - Chatfuel is the best bot platform for creating an AI chatbot on Facebook.
GetChat.App - Add WhatsApp chat to your website for free
Message Me - Website to create your contact business card
Smooch.io for Facebook Messenger - Message your customers from Slack, Front, a bot or anywhere!
Amazon Lex - Harness the power behind Amazon Alexa for your own conversational apps.
Avochato - Text messaging for your business.