![WARNING] This is Work-In-Progress project. Expect bugs.

Also it's build in cooperation with Claude Code and is only partially verified.

A Kotlin Multiplatform mobile application for reading and writing NFC tags on 3D printing filament spools using the OpenPrintTag standard.

OpenPrintTag is an open-source universal NFC standard for 3D printing filament spools, created by Prusa Research. It enables automatic filament detection and eliminates proprietary "smart spool" ecosystems through one interoperable standard.

• Universal Compatibility: One open standard that works across all brands and ecosystems
• Material Recognition: Automatically detect filament type, brand, and properties
• Live Tracking: Monitor remaining filament amounts in real-time
• Inventory Management: Track and log custom data for your filament collection
• Reusable Tags: Transfer tags between spools without vendor lock-in
• Offline Operation: No cloud dependency required
• Cost-Effective: Uses inexpensive NFC tags

This mobile app allows (when ready) users to:

• Scan NFC tags on filament spools to read material data
• Configure and write filament information to NFC tags
• Manage material classification (PLA, PETG, ABS, etc.)
• Set temperature profiles (print, preheat, bed temperatures)
• Track weight and material properties
• Store certifications and material tags
• Generate compliant OpenPrintTag NFC data

• Kotlin Multiplatform: Share code across Android, iOS, and Desktop
• Compose Multiplatform: Modern declarative UI framework
• Target Platforms:
  • Android (Primary target)
  • iOS (Arm64 & Simulator)
  • Desktop/JVM (Development and testing)

openprinttag-mobile/
├── composeApp/
│   └── src/
│       ├── commonMain/kotlin/     # Shared code for all platforms
│       │   ├── model/             # Data models (TagState, CountryCode, etc.)
│       │   ├── ui/                # UI components and theme
│       │   ├── App.kt             # Main app entry point
│       │   └── TagInfoViewModel.kt # State management
│       ├── androidMain/kotlin/    # Android-specific code
│       ├── iosMain/kotlin/        # iOS-specific code
│       └── jvmMain/kotlin/        # Desktop-specific code
├── iosApp/                        # iOS app wrapper
└── build.gradle.kts

• JDK 17 or higher
• Android Studio or IntelliJ IDEA with Kotlin Multiplatform plugin
• For iOS: Xcode (macOS only)

Build and run the Android app:

# macOS/Linux
./gradlew :composeApp:assembleDebug

# Windows
.\gradlew.bat :composeApp:assembleDebug

Or use the run configuration in Android Studio.

Run the desktop version for development and testing:

# macOS/Linux
./gradlew :composeApp:run

# Windows
.\gradlew.bat :composeApp:run

Open the /iosApp directory in Xcode and run from there, or use the run configuration in IntelliJ IDEA.

• Material classification selection (PLA, PETG, ABS, etc.)
• Basic information input (brand, material name, color, density)
• Temperature settings configuration
• Weight tracking
• Material properties and certifications
• NFC URL options
• Data validation and verification
• Desktop preview/testing support

• NFC tag reading functionality
• NFC tag writing functionality
• Filament inventory management
• QR code generation
• Material database integration
• Multilingual support

Contributions are welcome! This project follows the OpenPrintTag open-source initiative.

1. Follow Kotlin coding conventions
2. Use Compose best practices for UI components
3. Keep platform-specific code minimal (in platform folders)
4. Test on multiple platforms when possible

This app implements the OpenPrintTag specification. For more information:

• Official website: openprinttag.org
• Specification: Check the official OpenPrintTag documentation

This project is open-source. Please check the LICENSE file for details.

• OpenPrintTag Official Site
• Kotlin Multiplatform Documentation
• Compose Multiplatform

• Prusa Research for creating the OpenPrintTag standard
• The open-source 3D printing community