I need an Android application that helps students prepare for competitive exams through a flexible, engaging experience. Inside the app I want to create my own hierarchy of exams → subjects → topics and attach unlimited multiple-choice questions under each node. A simple in-app editor for adding or importing new questions is essential so I never have to rebuild the APK just to update content. Core functionality • Social media login only—no email or phone flows—so users can get started with a single tap. • Persistent user profiles that store scores, progress, streaks and any rewards unlocked. • Embedded YouTube videos (the app should feel like a mini YouTube client inside the preparation pages). • Ad placeholders wired to AdSense or a comparable network; I only need the hooks, not the ad account setup. • Real-time leaderboards and collectible achievement badges. These should update automatically as users clear quizzes or hit milestones such as “10 MCQs a day”. • Clean, modern UI with subtle animations or colour cues that celebrate right answers and gently flag wrong ones. Gamification & progression Each quiz session should award points, trigger badges, and push the user up a global leaderboard. I also want configurable daily / weekly targets (e.g., 10 questions per day) so learners receive streak notifications and see their goal status on the dashboard. Deliverables 1. Production-ready Android app (APK + Play-Store-ready bundle). 2. Full source code with clear, modular architecture so I can extend subjects or question banks later. 3. Brief admin guide showing how to add new exams, subjects, and MCQs, connect a YouTube video to a topic, and swap ad IDs. 4. Leaderboard and badge logic fully tested, including offline grace handling. 5. One round of post-delivery support for bug fixes. If you have prior experience with AdMob/AdSense, Firebase Social login, YouTube Android Player API, or similar stacks, that’s a big plus. Let me know what tech stack you propose, how long the build will take, and any recent examples of gamified learning apps you’ve shipped.