PhoneGap allows developers to create mobile apps using web technologies like HTML, CSS, and JavaScript. It works by packaging these web assets into a native mobile application using its framework. Developers can access device capabilities like the camera through PhoneGap's JavaScript API. APEX applications can be included in PhoneGap by specifying the APEX URL instead of index.html. Alternatively, APEX can be loaded in an iframe within the PhoneGap webview container. Images captured using the camera API can be uploaded to APEX as a CLOB by converting the base64 encoded image to a BLOB.