Cross-Platform Mining Lab Troubleshooter

I need a minimalist mobile app that helps technicians diagnose AAS/ICP spectrometer issues in the field. The core of the build will be a cross-platform codebase in Flutter or React Native, released on both iOS and Android.

Scope
• Integrate a ready-made backend such as Firebase or Supabase and connect it to a simple, searchable database.
• Allow users to filter by brand/model and enter an error code to view step-by-step troubleshooting instructions that I will supply in Excel format.
• Offer the three key functions selected—search error codes, access troubleshooting steps, and subscribe for premium features.
• Handle monetisation through an in-app paywall powered by RevenueCat with a monthly subscription.
• Deliver an extremely clean, minimalist UI/UX that performs well on modern iPhone and Android devices.

I will provide:
• The initial Excel sheet containing all error codes and resolutions.
• Brand assets, colour palette, and any copy required for onboarding or paywall screens.

You will deliver:
• Source code, fully commented.
• Two production-ready builds (App Store & Google Play).
• A brief hand-off document covering environment variables, build steps, and how to extend the database.
• A short demo video or TestFlight/Play Store beta link proving core flows.

In your proposal, include:
• A fixed-price quote and realistic timeline.
• Links to comparable apps you have shipped that demonstrate clean UX and in-app subscriptions.
• Your preferred stack (Flutter + Firebase or React Native + Supabase, etc.) and any relevant tooling.

I am ready to move quickly once the right developer is selected.