The document proposes developing a mobile app called UMBooks that allows University of Michigan students to buy and sell used textbooks based on specific courses. The app would organize textbooks by course to make trading more efficient. It would also focus on security and convenience by allowing secure signup with Umich emails and facilitating offline exchanges to avoid shipping fees. The proposed timeline is to draft designs in the first week, build the basic structure in weeks 2-3, and publish a beta version in the app store by week 8 to test before a final release in week 9.