Your on-chain proof of real-world attendance
SOLTAG is a privacy-first mobile dApp that mints non-transferable NFT credentials (Soulbound Tokens) to prove you attended real-world events. It achieves this without strictly tracking users or storing raw GPS coordinates on-chain, ensuring complete user privacy.
Designed for robust verification at conferences, meetups, gyms, and DAO governance events on Solana.
| Field | Value |
|---|---|
| App NFT Address | 2Aev3so3mosy9XoJrZ6u3QRfNzUgUv8upmxY2mHgGesp |
| Publisher Wallet | 9hLa7kGEkRYNpRbwcFT5w9ncg291VHLcSh5sQEgpM8B4 |
| NFT Type | Metaplex Master Edition |
| Website | soltag-app.vercel.app |
| Minted | Dec 18, 2025 |
| dApp Store Status | ✅ Submitted for Review |
The Problem Traditional attendance tracking relies on centralized databases (sign-in sheets, Web2 apps) which are prone to data leaks, or they require invasive GPS tracking that compromises user privacy. Furthermore, simple POAPs can often be minted from anywhere, failing to prove physical presence.
The SOLTAG Solution Soltag verifies physical presence through a multi-layered approach:
- Zone Validation: The app locally verifies if the device is within the event's geofence (using privacy-preserving geohashes) before allowing a scan.
- Cryptographic Proof: Scanned QR codes contain a signed payload that expires quickly, preventing replay attacks.
- Hardware Attestation: (On supported devices) The app leverages the Solana Seeker's Secure Element to prove the request originates from a genuine, uncompromised device.
- Privacy-First Onboarding: No email, phone number, or social login required. Users simply connect their Solana wallet.
- Hardware Integration: Fully optimized for Solana Seeker, utilizing the Seed Vault for signing and the Secure Element for device attestation to prevent bot farming.
- Offline Support: Built with an "Offline First" architecture. Users can scan and verify codes even with spotty connectivity; transactions are queued and submitted when online.
- Modern UI: A sleek, high-performance interface built with React and Ionic/Capacitor, featuring Dark Mode and glassmorphism transparency effects using Lucide React icons.
- Global Rankings: Users gain reputation points for every verified event, competing on global and monthly leaderboards.
- Seeker Verification: Exclusive visual indicators (Shield Badge) for users verifying via Seeker hardware, establishing a higher tier of trust.
- Profile Customization: Users can set a local username and avatar. This data is stored on-device to respect privacy, while the wallet address serves as the global identifier.
- QR Validator: Implements Ed25519 signature verification on QR payloads to ensure they were generated by the event organizer.
- Secure Storage: Uses AES-GCM encryption to store sensitive session keys and wallet adapters locally.
- Zone Privacy: Location verification uses Geohash precision level 5 (~5km radius) combined with SHA-256 hashing. Raw GPS coordinates are never sent to the server or blockchain.
| Feature | SOLTAG |
|---|---|
| Blockchain | |
| Fees | Ultra-low (~$0.00001) via Compressed NFTs |
| Mobile-First | Native Android/Saga |
| GPS Privacy | Hashed & Local-Only |
| Hardware Attestation | Seeker ID Integration |
| Offline Support | Queue System |
| Soulbound | Enforced On-Chain |
| Open Source |  |
Built natively for the Solana Mobile ecosystem:
Mobile Wallet Adapter (MWA)
- Provides a native signing experience without context-switching to browser wallets.
- Supports seamless deep-linking with Phantom and Solflare.
Seeker Hardware-Ready
- Integrates with the Seeker device attestation service.
- Hardware-backed anti-fraud measures ensure high-integrity attendance data.
Frontend
Solana Integration
Security
Prerequisites: Node.js 18+, Android Studio / SDK.
# 1. Clone & Install
git clone https://github.com/soltag/soltag.git
cd soltag-app
npm install
# 2. Run Web Development Server
npm run dev
# 3. Build for Android
npm run build
npx cap sync android
cd android && ./gradlew assembleDebugFor Event Attendees
- Connect Wallet: Launch the app and connect via MWA (Phantom/Solflare).
- Scan: Use the integrated camera scanner to scan the event QR code.
- Verify: The app locally validates the event signature and your geohash.
- Mint: Approve the transaction to mint your Soulbound Token credential.
For Organizers
- Generate cryptographically signed QR codes for your events.
- Gate DAO voting, Discord channels, or airdrops based on proven real-world attendance.
- Phase 1 (Complete): Mobile App, Offline Queueing, Basic Security Layer.
- Phase 2 (Current): Seeker Hardware Integration, Global Leaderboards.
- Phase 3 (Next): Anchor Program Deployment (Devnet/Mainnet), Metaplex Compressed NFT Integration.
License: MIT Support: Open an Issue
Built with ❤️ on Solana Proving real-world presence, preserving privacy.