Developing a web app involves turning your idea into a reality. First, solidify your concept and research the market to see if it fills a gap. Then, define its features and plan the user experience. With a clear vision, design mockups and prototypes to test the usability. Now it's time to build! Develop the front-end users see and the back-end that powers it. Finally, launch your web app, ensuring it's hosted on a platform for users to access it.