An installable app for the real table
Okey 101 Scoreboard
An app that replaces the paper scorecard for Okey 101 played at a real table. You enter who finished, how, and the tiles left in hand; penalties and totals follow the rules. It installs like an app, opens without a connection, and the rest of the table follows the score live on their own phones via a QR code.
- Status
- Live
- Tools
- Next.js 16 · React 19 · TypeScript · PWA · Service Worker · Upstash Redis · Vitest · Playwright
The problem
Paper scorecards invite arithmetic slips and long rule debates: finishing with the okey doubles penalties, opening with pairs doubles a hand, players who never opened take a fixed penalty. The app is used at the table, often on a weak connection and one-handed, so it had to be fast, exact and work offline.
My role
Sole developer: scoring rules, interface, offline support, the live-sharing service and tests.
Approach
- 01
Rules in one place, tested
Finish types, multipliers and optional penalties live in one pure TypeScript module; the UI only renders results. House-specific values are adjustable in settings, and every finish type is covered by unit tests.
- 02
Installs and opens offline
It has its own manifest and icons for the home screen. A service worker caches the page and its loaded assets; offline it opens the last version and announces updates when they arrive. The game is stored on the device, so a refresh never loses the table.
- 03
Fast one-handed entry
On phones a custom number pad with a “next player” key replaces the system keyboard; a saved hand can be undone from the toast, and the screen stays awake during play. Finished tables are kept in history with per-player statistics.
The hard part
Live viewing without a socket server
The hosting doesn’t suit long-lived connections. The scoring phone sends a snapshot of the table on every save; viewers poll every 4 seconds and get a body-less 304 when nothing changed, and stop polling in background tabs. The write key stays on the sharing device and the server keeps only its SHA-256 hash; links expire after two days and creation is rate-limited per IP.