AI Receipt Scanner App

I’m building a cross-platform mobile app in React Native that lets users snap a photo of any receipt and immediately see the key figures—vendor, date, total, tax, and full line-item breakdown—pulled out by GPT-4 Vision. The structured data must be returned through LangChain with a Pydantic model so every field lands in predictable JSON without hallucinations.

Once the data is validated, the app should push it straight into a connected Google Sheets document through the Sheets API. If the device is offline, the photo and pending payload stay in a local queue, then sync automatically when connectivity returns.

To keep costs low and latency tight, each image needs to be compressed on-device before it ever reaches OpenAI. I also want robust error handling: retry logic on failed external calls, graceful user notices for timeouts or network drops, and clear logging so I can trace issues in production.

The backend will run as lightweight serverless functions—happy to deploy on Vercel or AWS Lambda, whichever integrates more smoothly with your workflow.

Deliverables
• React Native iOS + Android app with camera capture, local queue, and offline syncing
• GPT-4 Vision integration wrapped by LangChain & Pydantic for zero-hallucination JSON
• Image compression pipeline tuned for minimal quality loss
• Google Sheets API connector with secure token storage
• Serverless backend functions (TypeScript or Python) with full CI/CD setup
• Comprehensive error and retry strategy, plus concise documentation for hand-off

If you’re a senior developer who has already shipped AI-driven mobile experiences and you’re fluent with React Native, OpenAI endpoints, and Google Sheets, I’d love to start right away.