Attend for iOS & Android

The mobile companion app for Attend, Hack Club's event attendance platform. Organizers use it to check participants in at the door; participants use it to carry their tickets.

Built with Expo / React Native, with native Swift modules for Live Activities and Apple Wallet.

What it does

For organizers:

• QR check-in — scan participant QR codes (attend:P:{uuid}) for instant check-in
• NFC badges — write and scan NFC badges for tap-to-check-in
• Offline-first — scans queue locally when offline and sync automatically when connectivity returns
• Participant search & filtering — Airtable-style filtering across the participant list, with medical alerts (anaphylaxis risk, high support needs) surfaced prominently
• Emergency contacts — tap-to-call from a participant's detail view
• Airport mode — live view of participants in transit: flight legs, arrival status, and unaccompanied-minor pickup tracking
• Kiosk mode — PIN-locked self-serve check-in station for a spare iPad at the door
• Biometric lock — Face ID / Touch ID gate on sensitive participant information

For participants:

• My tickets — view event tickets with QR codes
• Apple Wallet — add tickets as Wallet passes
• Live Activities — event-day status on the Lock Screen and Dynamic Island
• Push notifications — event updates from organizers

Getting started

Prerequisites

• Node.js 18+
• Xcode (for iOS) or Android Studio (for Android)
• An Attend account

Note

The app uses native modules (NFC, Live Activities, Wallet), so it will not run in Expo Go — you need a development build.

Setup

npm install

Create a .env.local with your backend and OAuth config:

EXPO_PUBLIC_API_URL=http://localhost:3000
EXPO_PUBLIC_OAUTH_CLIENT_ID=your-oauth-client-id

Then build and run a development client:

# iOS
npx expo run:ios

# Android
npx expo run:android

Scripts

npm test           # jest
npm run lint       # eslint
npm run typecheck  # tsc --noEmit

Project structure

src/
  screens/     one file per screen (scanner, kiosk, airport mode, tickets, ...)
  services/    api client, auth, offline sync, NFC, notifications, storage
  hooks/       useScanner, useParticipants, useNFC, useAuth, ...
  components/  shared UI
modules/
  activity-controller/  native Swift module for starting/updating Live Activities
  wallet/               native Swift module for adding Apple Wallet passes
targets/
  widget/      WidgetKit extension rendering the Live Activity

The backend is a Rails app that serves the API this app talks to, handles OAuth, and issues Wallet passes.

Releases

Builds and submissions go through EAS — see eas.json for the profiles. JS-only changes ship over the air:

bin/ota "what changed"

The bin/ota script temporarily stashes local .env files so development values never leak into a production bundle.

Contributing

Contributions are welcome! If you've found a bug or have an idea:

1. Open an issue first for anything non-trivial so we can talk it through
2. Fork the repo and create a branch for your change
3. Make sure npm test, npm run lint, and npm run typecheck pass
4. Open a pull request with a clear description of what changed and why

If you're at a Hack Club event and something in the app breaks, an issue with steps to reproduce is hugely appreciated — even if you don't have time to fix it yourself.

License

GPL-3.0