I want this app to earn its keep through penjualan dalam aplikasi, specifically by offering barang digital—e-books—to users. What I need is a seamless end-to-end setup that lets a reader browse, purchase, download, and read titles without ever leaving the app. The scope • Integrate the full in-app purchase flow for e-books, compliant with both Apple App Store and Google Play policies. • Build or wire up a lightweight catalogue where I can upload, price, and update my e-book files and metadata. • Ensure secure delivery and DRM/locking appropriate for digital content. • Add basic sales analytics so I can track volume, revenue, and top-selling titles. • Hand off clean, well-commented code plus a short setup guide so I can manage new releases on my own. Acceptance I’ll consider the job done when I can install a test build, see at least one sample e-book offered for sale, complete a sandbox purchase, download it, and open it from the in-app library without errors. If you’ve tackled in-app purchases for digital goods before—especially e-books—let’s talk.