Smooch.io for Facebook Messenger - Message your customers from Slack, Front, a bot or anywhere!
Octane AI - Octane AI offers tools to create a bot and engage customers and audience via messaging.
VECA - Your eCommerce assistant
Gomix - The easiest way to build the app or bot of your dreams
Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.
Rasa Core - Rasa Core is a well-designed dialogue engine used to create chatbots.