Receipt-to-warranty tracker

The idea

A mobile-first web app where you photograph a receipt the moment you get home from a purchase. A vision model extracts the merchant, item, price, purchase date, and warranty period (if printed). The app stores the receipt image, indexes the metadata, and sends you a single push notification a week before each warranty expires. Optional: surface the merchant's return window separately, since it's almost always shorter than the manufacturer warranty.

Why build this

Everyone loses receipts. Warranties expire silently. Apps that try to solve this today are either glorified file folders (Genius Scan, Evernote) or trying to be expense trackers (Expensify) — none of them actually understand what's on the receipt or proactively remind you. Vision models are now good enough that the parsing step is essentially free, which kills the previous moat (manual data entry).

Stack sketch

• Frontend: Next.js + React, installable PWA so it works like a native camera app.
• Image capture: browser <input capture="environment"> + client-side cropping with react-easy-crop.
• OCR + extraction: Claude Sonnet 4.6 with structured output (JSON schema for merchant, items, total, purchase_date, warranty_days, return_window_days).
• Storage: Supabase — Postgres for metadata, Storage bucket for receipt images.
• Reminders: Web Push via VAPID, scheduled with a daily Postgres pg_cron job that fans out notifications.
• Auth: Supabase magic link.

Scope for v1

In: - Capture/upload a receipt photo. - Extract structured data, show it in an editable form before save (the user is the safety net for OCR errors). - List view of all receipts, sortable by warranty expiry. - Web push reminder 7 days before warranty ends.

Out: - Multi-user sharing (households). - Expense categorization or budgeting. - Email-forwarding for digital receipts (tempting, but kill scope creep — phase 2).

Where it could go

The natural next move is email ingestion: a unique forwarding address (u_abc123@inbox.app) that auto-imports digital receipts from Amazon, Shopify stores, and DoorDash. After that, the dataset starts becoming valuable on its own — you can offer a "what should I return?" view that flags items still inside their return window, or a "warranty claim assistant" that drafts the email to the merchant when something breaks.

A more ambitious branch: partner with a credit card issuer that already offers extended warranty coverage, and make the app the proof-of-purchase shoebox that turns that perk from theoretical into actually-claimable.

Watch out for

OCR accuracy on crumpled thermal receipts is the user-trust make-or-break — always show the extracted fields for confirmation before saving, and never silently auto-file. Also: warranty terms are often not printed on the receipt at all (just on the box or the manufacturer's site), so plan for a graceful "warranty unknown — set manually?" path on day one.