An open-source Android and iOS app for keg tap-handle labels on battery-free NFC e-paper tags. Pick what's pouring, preview the label, tap your phone to the handle, and the label stays after you walk away.
Made for homebrewers and just as at home in a taproom. It writes to Waveshare's 2.7" NFC-powered e-paper today, and can write any image for custom labels.
Preview, write, done, with a sample label and a simulated tag. Screenshot tests generate these; see CONTRIBUTING.md.
| Preview | Writing | Done | |
|---|---|---|---|
| Android |  |
 |
 |
| iOS |  |
 |
 |
- Reliable writes. Generous timeouts, clear progress, a completion check and clean retry.
- Native feel. SwiftUI on iOS and Jetpack Compose on Android, over a shared Kotlin Multiplatform core.
- Minimal permissions. NFC and the photo picker. No network, accounts or telemetry.
Early development. See USAGE.md for supported displays and how to try a development build.
- CONSTITUTION.md: mission, principles, non-goals
- CONTRIBUTING.md: building, testing, layout
- SECURITY.md: reporting a vulnerability
- PRIVACY.md: privacy policy; the app collects no data
- docs/architecture/: design and tag protocols
- docs/decisions/: decision records
- docs/guides/: how-tos
- docs/operations/: CI, releases and the hardware test log
Apache License 2.0. See NOTICE for attributions.