Senior React Native / Flutter developer – iOS & Android audio app (Supabase)

Hello, I'm looking for a senior React Native or Flutter developer to build the v1 of an iOS & Android app. A working prototype already exists with first users. The product: record voice messages, store them securely, and pass them on to a trusted person. Main technical points: - Reliable audio recording (AAC, up to 60 min, works with the screen locked, automatic draft if interrupted) - Supabase back-end (EU region, Paris), strict per-user access rules (RLS), S3-compatible audio storage that can be migrated later - Sign in with Apple and Google, Face ID / fingerprint lock - Annual subscription and one-time purchases through the stores (RevenueCat or equivalent) - Share links with deep links, and a flow to designate a trusted person What I provide: complete specifications, mockups of every screen, brand guidelines and ready-to-use illustrations. What I expect: - 2 or 3 apps you have published on the App Store / Google Play - A fixed-price estimate split into milestones, with a timeline - Code hosted on my GitHub account from day one, with full transfer of rights - An indicative rate for maintenance after launch How I like to work: weekly progress update, a testable build at the end of each milestone, clear written communication. Detailed specifications will be shared after signing an NDA. Developers based in Europe preferred (time zone). Please start your proposal with the word "VOICE" so I know you've read the brief.