Twilio - Brings voice and messaging to your web and mobile applications.
Chatfuel - Chatfuel is the best bot platform for creating an AI chatbot on Facebook.
MessageBird - Reach 7 billion phones in seconds via SMS, Chat & Voice. Try it for free and improve your communication.
Landbot - An intuitive no-code conversational apps builder that combines the benefits of conversational interface with rich UI elements.
Nexmo - Nexmo is a simple two way SMS API with global reach and wholesale rates
ChatBot - Easy to use chatbot platform for business