This tutorial guides developers through building a screen pop application using Twilio Client and FullContact API. The application allows users to input their name, which is then used to look up caller information using the FullContact API. When an incoming call is received, the application displays the caller's details to the user, who can accept or reject the call. The tutorial covers setting up a Node.js application with Twilio Client and FullContact API integration, creating views for the index and client pages, handling incoming calls, and configuring environment variables and TwiML app settings. Once completed, the application allows users to receive calls from a dedicated phone number and view caller information in real-time.