Developing PhoneGap application requires a workflow. All the tools and developer’s workflow is important to get an app on the devices. The most important thing is to have an idea of what you want to build.
The wireframes/ UX designs or sketches help to understand what the application will accomplish from a user’s point of view. It will be from the HTML level to figure out how the DOM elements should be positioned. It will also assist in gauging the complexity of a project. There are questions like how many moving parts are there, how all the elements need to work and much more. This design can be used as a leverage to figure out the needs of the application.