Cross-Platform Productivity App Development

I want to transform a clear-cut productivity concept into a smooth, reliable mobile experience delivered on both Android and iOS. The full cycle—design, build, test, and store submission—should come together under one roof, ideally through a shared codebase such as Flutter or React Native so users on either platform enjoy the same speed and polish.

What I need
• A clean, modern interface that feels native on each platform.
• Secure, cloud-based user accounts to keep data in sync.
• Well-documented, maintainable code stored in a private Git repository.
• Integrated analytics, crash reporting, and an in-app feedback channel.
• Step-by-step guidance through Google Play and App Store review, including screenshots and release notes.

Deliverables
1. Clickable UI prototype (Figma or similar) approved before coding starts.
2. Production-ready Android (AAB) and iOS (IPA/TestFlight) builds.
3. Complete source code with build instructions.
4. One month of post-launch bug-fix support.

Acceptance criteria
• App passes both store reviews.
• No critical or high-severity crashes in the first 100 live sessions.
• All user-visible text free of spelling or grammar errors.

If you have a track record of shipping productivity apps, please share store links and outline the tech stack and timeline you’d use for this project.