Android RFID Wallet App Development

I'm looking for an experienced Android developer to create a standalone RFID wallet application with robust features and security measures.

Key Features:
1. Card Management:
- Issue new RFID cards via NFC or external reader
- Assign user profiles or ID numbers
- View card history and balance

2. Balance Operations:
- Admin top-up via app
- Manual balance deduction on purchases
- Set limits, expiry dates, and usage restrictions

3. Admin Dashboard:
- Real-time transaction logs
- User management (e.g., cafeteria staff)
- Reports on daily usage, top-ups, and low balance alerts

4. Hardware Integration:
- NFC-enabled Android devices for reading/writing cards
- Optional support for external USB RFID readers
- Compatibility with MIFARE Classic and NTAG cards

5. Security & Offline Mode:
- Access via PIN or biometric
- Offline sync for poor connectivity areas
- Encrypted local storage for sensitive data

Ideal Skills & Experience:
- Proficiency in Android development
- Experience with NFC and RFID technologies
- Strong background in implementing secure authentication methods
- Familiarity with offline data synchronization

Please provide a portfolio showcasing similar projects. Looking forward to your bids!