In a Cordova-based Ionic app, storing photos involves using the Ionic Native Camera plugin to take photos and the Ionic Native File plugin to save them to the app's filesystem. The process begins by configuring the camera to save images as temporary files using the FILE_URI destination type, avoiding memory-intensive base64 encoding. Once a photo is captured, it is initially stored in the app's temporary storage and needs to be moved to permanent storage using the File plugin to prevent deletion when the app closes. This involves extracting file paths and copying the image to a more secure directory. To display the image within the app, it must be converted from a device file path to a local HTTP server path using the Ionic Native WebView's convertFileSrc method, and Angular requires additional URL sanitization. The tutorial provides a step-by-step guide with code snippets and references to additional resources for further exploration of Cordova and Capacitor plugins.