What are some alternatives?
When comparing Amazon Lex and Dialogflow, you can also consider the following products
IBM Watson Assistant - Watson Assistant is an AI assistant for business.
Chatfuel - Chatfuel is the best bot platform for creating an AI chatbot on Facebook.
Tars - TARS enables users to create chatbots that replaces regular old webforms.
Botpress - Open-source platform to create, manage and extend bots
Verloop - Verloop is a multi-channel customer support and engagement automation chat system.
Microsoft Bot Framework - Framework to build and connect intelligent bots.