Compare two offers by cost per comparable size and immediately see which one gives you more for your money. Betterbuy is private, local-first, and works offline.
- Open Betterbuy in Chrome on your iPhone.
- Tap the Share icon (the square with an upward arrow).
- Scroll down and tap Add to Home Screen.
- Optionally rename the app, then tap Add.
Betterbuy will appear on your Home Screen and open like a native app. If Add to Home Screen is unavailable in Chrome, update Chrome or use Safari and follow the same steps.
npm install
npm run devThe app uses React with a small Zustand reducer store. See Zustand DevTools time travel for the development debugging workflow and its persistence boundaries.
The calculator uses Tailwind CSS with Betterbuy theme utilities. Use Storybook to review documented component states and run their interaction tests.
npm run storybook
npm run test:storybooknpm run typecheck
npm test
npm run test:coverage
npm run build
npm run test:e2eBetterbuy uses vite-plugin-pwa to generate a revisioned service worker from
Vite's final hashed HTML, JavaScript, CSS, and install assets. This keeps the
cached HTML shell and its referenced assets version-matched after a deployment,
instead of leaving installed users on a static service worker that does not
change with ordinary application builds.
The PWA manifest and service-worker generation are configured in Vite; React handles runtime registration and the update UI. Updates download in the background and apply only after the user selects Update now, so a draft comparison is not interrupted.
Enter offers using comparable sizes—Betterbuy does not convert units or collect data. Saved comparisons stay in local browser storage, can be restored, pinned or unpinned (up to 5 pins), or deleted, and are capped at 50 entries.