AWS service for building conversational chatbots and voice assistants. Like having the technology behind Alexa available for your own applications.
A bank creates a chatbot using Lex that helps customers check account balances and transfer money.
All four are managed conversational AI platforms for building chat/voice bots. Lex is tightly integrated with AWS (Lambda, Connect) and uses NLU to map user input to intents and slots. Azure AI Bot Service is a bot hosting/orchestration layer that commonly uses Azure AI Language (CLU) or other NLU. Dialogflow is Google’s NLU-centric agent builder with strong telephony/contact-center integrations. OCI Digital Assistant provides intent-based assistants integrated with Oracle apps and channels.