PhoneGap is an open source framework that allows developers to create mobile apps using standardized web technologies like HTML, CSS, and JavaScript. It works by including web code in a native mobile project, and using Apache Cordova to expose native device APIs to the web code through JavaScript. Cordova is the underlying platform that PhoneGap is built on top of, providing access to device functionality through JavaScript APIs. PhoneGap supports creating apps for many mobile platforms from a single codebase.