To send SMS from an iOS app using Swift, it's recommended to create a backend application that implements the Twilio REST API and wraps up your credentials to avoid security issues. Using Python on the backend, you can use Flask or another server-side library to build a small application that handles webhooks and sends SMS messages. The iOS app can then send requests to this backend using Alamofire, specifying the correct headers and parameters for the POST request. This design allows you to reuse your Python code on other platforms and tackle various communication challenges with Twilio's services, such as IP Messaging, Video, or Client.