The document provides instructions for using the AltPhone application, which allows iPhone users to make low-cost international calls. It explains how to download, install, and configure AltPhone, and how to make calls using different methods like VOIP, callback, or call-in to save money. The guide also covers how to select call-in numbers, enable VOIP over 3G, send SMS, add funds to your account, and where to find more support information.