Bookexg is an Android app that allows users to exchange books for free or at a low cost. It works by matching book donors with acceptors who can then exchange books either through a courier service or by meeting in person. The startup aims to build a large user base to earn profits from advertisements in the free version of the app. Its strategy is to target students and avid readers by offering a simple, lag-free interface for unlimited swaps in the premium version or 3 free swaps per month otherwise. The implementation plan outlines developing an initial version, testing it in select markets, modifying it based on feedback, and officially launching in the Google Play Store.