The guide outlines the necessary steps for updating Ionic apps to ensure compatibility with iOS 11 and the iPhone X, focusing on the use of UIWebView and WKWebView. It emphasizes updating to the latest versions of ionic-angular and Ionic 1 to address the iPhone X's safe regions and viewport changes, with instructions for modifying the viewport meta tag to utilize the entire screen space. WKWebView is being promoted as the new default webview for Ionic apps due to its improved support for the iPhone X, and developers are encouraged to update their plugins and test the recent fixes. Additionally, the guide provides details on the new requirements for app icons and splash screens in Xcode, including generating these resources using the Ionic CLI, and highlights the importance of updating the cordova-plugin-statusbar for compatibility. The document also invites developers to report any issues encountered during the update process and sign up for the newsletter for further updates.