Native iOS and Android members app for premium parenting education (community & cohort dashboard)

We are The Confident Learning Co., a UK parenting education brand. We run a paid monthly membership community (Growing Together) and premium eight-week family coaching programmes. We need an expert mobile developer to build our members-only native app for iOS and Android from a written specification pack we will provide, using a cross-platform framework (Flutter or React Native preferred) so one codebase serves both stores. What you will build: Member sign-in where access is granted by purchases made on our website via Stripe (webhook-driven entitlement, integrated with Kit, our email platform, for tagging). Strictly no in-app purchases anywhere in the app. Community spaces: five group feeds with posts, comments, reactions, pinned posts, and moderation tools for two admins. A sequenced content library (video, PDF, written lessons) released in a fixed order. Private cohort spaces for our coaching programmes, invisible to standard members. A progress dashboard: coaches see per-family lesson completion and weekly check-ins; each family sees their own progress through their eight-week programme. Admin-controlled push notifications. Live sessions via an embedded third-party service such as Zoom or Mux. You are not building livestreaming infrastructure. Sole branding throughout: our logo, our colours, App Store listing name "The Confident Learning Co.", home screen label "TCLC". We will hold our own Apple and Google developer accounts; you handle submission through them. Skills required: Flutter or React Native, native iOS and Android delivery, Stripe API and webhooks, push notifications (Firebase/APNs), REST API integration, secure authentication, GDPR-compliant data handling, App Store and Google Play submission experience. Show us two apps live in both stores today that you built as sole or lead developer. How we work: You will receive a complete specification pack with numbered requirements and an acceptance checklist, so expectations are precise from day one. Work is milestone-based with payment released per accepted milestone: (1) clickable design prototype, (2) authentication and Stripe entitlement, (3) community and content library, (4) cohort spaces and progress dashboard, (5) push and live integration, (6) store submission, testing and handover documentation. Code lives in our GitHub repository from week one, not handed over at the end. Full IP assignment and code ownership pass to us upon final payment. We communicate in writing through Upwork, with a short weekly progress call; we give specific, fast feedback; and we expect problems to be raised early rather than worked around silently. GDPR compliance and UK data handling are mandatory. Your proposal must include a written monthly maintenance retainer for post-launch support, including OS updates, and an answer to this question: what happens to our project if you become unavailable for a month? Screening questions: Link two apps live in both stores today that you built as the sole or lead developer. What was your role, exactly? Describe how you would grant and revoke app access from a Stripe webhook, in plain terms. What stack would you use for this build and why? What is your monthly maintenance retainer for an app like this, and what does it cover? What happens to our project if you become unavailable for a month?