Full-Stack Mobile App Developer for Party Game App Front-End, Backend, Subscriptions & Launch

I am looking for a reliable full-stack mobile app developer to help continue development on an existing culturally rooted Ethiopian party game app and prepare it for closed testing and App Store / Google Play launch. This is a mobile party/social game, not a visually heavy 3D or animation-heavy game. The gameplay is more prompt/card-based, social, and culturally driven. The app is part of Bereka, a social gaming brand focused on Ethiopian and diaspora experiences, language, humor, and informal play. Familiarity with Ethiopian/Amharic culture is a plus, but not required if you are thoughtful, detail-oriented, and willing to understand the product context. Part of the front end has already been developed by another developer. I need someone who can review the existing codebase, understand what has already been built, continue the front-end/backend work, implement key launch features, document everything clearly, and help prepare the app for publishing. I am looking for someone who is communicative, available, and consistent. I prefer a developer who can give clear progress updates, ask questions when requirements are unclear, document their work, and stay responsive during the milestone timeline. This project may lead to longer-term work if the first phase goes well. Core Responsibilities: Review the existing mobile app codebase and identify what is complete, incomplete, or risky Continue front-end development from the existing work already completed by another developer Set up or improve backend services and database structure Integrate or complete Battle Mode / party game functionality Implement authentication, persistent sessions, logout, and user profiles Build referral system, signup attribution, and referral/history logs Add free vs. premium access control Set up subscription/access status fields Add payment/subscription status validation foundation Create or improve database security rules and backend access protections Prepare the app for Google Play internal/closed testing Prepare the app for Apple TestFlight testing Support App Store / Google Play launch readiness Fix priority bugs related to the agreed milestone scope Provide clear documentation for setup, backend/database structure, changed files, testing notes, known issues, and recommended next steps Expected Milestones: Codebase Review + Backend Foundation + Battle Mode Integration Auth, Persistent Sessions, Logout + User Profiles Referral System + Signup Attribution + History Logs Subscription Access Control + Payment Status Validation Testing, Documentation + App Store / Google Play Launch Support Required Skills: Full-stack mobile app development experience Experience working with an existing codebase Front-end mobile app development experience Backend/database setup experience Authentication and user profile implementation Referral, subscription, payment, or premium access-control experience Ability to test Android and iOS builds Ability to support closed testing and app store launch readiness Clear written communication and documentation Nice to Have: Flutter experience Firebase / Firestore experience Experience with in-app purchases or subscription access Experience with payment gateway integration Experience with mobile games, party games, social apps, or card/prompt-based apps Experience with Google Play Console and Apple TestFlight Experience with Ethiopian payment systems such as Chapa Familiarity with Amharic, Ethiopian culture, or diaspora-focused products Work Style / Communication Expectations: Please be available for consistent communication during the project. Please provide clear updates on what was completed, what is blocked, and what you need from me. Please ask questions early instead of making major assumptions. Please document technical decisions and changed files/features as work is completed. Please communicate any risks, delays, or scope concerns early. I value reliability, clarity, and thoughtful problem-solving more than rushed work. Time Commitment: This is a fixed-price milestone-based project, but I expect the developer to have enough availability to make steady progress each week. Based on the current scope, I expect this to require a meaningful part-time commitment during the project timeline, not just occasional small edits. Please only apply if you have the availability to review the codebase, implement features, test, revise, and communicate consistently. please include any relevant projects in your proposal.