Receive an SMS Delivery Receipt with Ruby on Rails

This tutorial builds on the previous "Getting Started with Nexmo SMS and Ruby on Rails" series by explaining how to know when an SMS has been delivered, specifically receiving Delivery Receipts from Nexmo. To do this, developers need to set up a webhook endpoint using tools like ngrok to make their local server accessible to Nexmo, and configure the Nexmo dashboard to forward these receipts to that endpoint. Once set up, Nexmo will notify the application with a DLR containing information about the delivered message, which can then be processed and updated in the database with the new status, allowing developers to track the delivery of their SMS messages.