This ASP.NET application uses Twilio to connect incoming phone calls to other phone numbers based on the caller's location. The application allows users to dial in and be routed to a regional office or directed to a survey after their interaction with customer service. In this tutorial, we've learned how to build a call forwarding system using C# and ASP.NET MVC, with Twilio as the API provider. We've covered key points such as setting up a Twilio account, configuring the application, handling incoming calls, verifying state information, and routing users to their senators' offices. The application is built using a combination of Razor views, controllers, models, repositories, and TwiML endpoints. We've also seen how to handle missing state information, forward calls to multiple senators, and end calls with a thank-you message. With this tutorial, developers can create their own call forwarding systems that seamlessly route users to the right resources based on their location.