Flatsby

Shared shopping lists, split expenses, settled debts. Household management for people living together.

flatsby.com

Flatsby is one household in one place: everyone sees the same lists, the same expenses, and the same balances, on web, iOS, and Android. The screenshots on this page are captured automatically from the real app on every release.

Shopping lists

Everyone in the household shares the same lists. When a flatmate checks off the milk in the supermarket, you see it the next time you open the list. Items carry categories and who added them.

Expenses and settling up

Log what you paid, split it equally, by percentage, by shares or by exact amounts, and Flatsby keeps a running balance per flatmate. Settlements clear debts between two people.

Calendar

Chores and events for the whole household. Repeat them daily, weekly, monthly or yearly, and pick several flatmates to take turns. Tick a chore off and everyone sees who did it.

AI assistant

Ask about your household in plain language. The assistant reads your lists and expenses, answers with charts and tables, and can add items or expenses for you.

Groups

A group is your household. Invite flatmates with a link, QR code or short code, manage roles, and keep every list and expense scoped to the people who share the flat.

Tech

TypeScript monorepo. The tRPC API lives inside the Next.js app, so the web app is also the backend for both clients.

• Web: Next.js, React, Tailwind, shadcn/ui, deployed on Vercel
• Mobile: Expo / React Native, NativeWind, Expo Router, built with EAS
• API: tRPC with shared Zod validators
• Data: PostgreSQL (Neon) via Drizzle ORM
• Auth: Better Auth (Google and Apple sign-in)
• Tooling: Turborepo, pnpm, Biome

apps/expo        Expo app, iOS and Android
apps/nextjs      Next.js web app, and the tRPC API
packages/api     tRPC routers, procedures, group access helpers
packages/auth    Better Auth config, shared by both clients
packages/db      Drizzle schema and migrations
packages/chat    AI chat feature
packages/ui      Shared web components, shadcn based
packages/validators  Shared Zod schemas
tooling/         Shared configs and the GitHub Actions setup

Development

Node and pnpm versions come from .nvmrc and the packageManager field in package.json.

pnpm install
cp .env.example .env   # then fill in the values
pnpm db:migrate
pnpm dev               # web + mobile in watch mode, or pnpm dev:next for web only

Before committing: pnpm check and pnpm typecheck. Working conventions for this repo live in AGENTS.md, and how to propose a change in CONTRIBUTING.md.

Releases are fully automated: merging a release PR tags the version, builds both apps, submits them to the stores, and recaptures every screenshot in this README from the released code.

License

MIT, see LICENSE. Built on the T3 Stack and create-t3-turbo.