Napkin

A native Apple personal finance calculator for macOS and iOS. Track credit card balances, manage subscriptions, and calculate optimal payment strategies. CloudKit sync keeps your data in sync across all your devices.

Here's me flipping around the different views using demo data:

napkindemo_compressed.mov

Features

Account Management

• Track multiple credit cards, loans, mortgages, and asset accounts
• Support for APR tracking (fixed and variable rates)
• Credit limit and utilization monitoring
• Payment due dates and minimum payment calculations

Smart Payment Strategies

• Debt Avalanche: Prioritize highest APR accounts first
• Debt Snowball: Pay off smallest balances first
• Intelligent payment planning with paycheck timing
• Shortfall protection for upcoming payment periods

Financial Dashboard

• Credit utilization
• Net Worth breakdown
• Monthly payment minimums calculation
• Historical net worth trends with interactive charts

Subscription Tracking

• Manage recurring expenses by category
• Flexible frequency options (what do you pay, how many times per year do you pay that)
• Cost breakdowns and category totals
• Active/inactive subscription management

Data Management

• Import/export functionality for all data
• Settings management including prime rate adjustments
• iCloud sync via CloudKit across all your devices
• Clean, native Apple interface for macOS and iOS

System Requirements

• macOS: 14.0 (Sonoma) or later
• iOS: 18.0 or later (iPhone and iPad)
• Xcode: 15.0+ (for building from source)
• Swift: 5.9+
• iCloud account: Required for CloudKit sync between devices

Project Structure

napkin/
├── napkin/
│   ├── Models.swift          # Core data models
│   ├── ContentView.swift     # Main app interface  
│   ├── AccountListView.swift # Account management
│   ├── SettingsView.swift    # App preferences
│   └── ...
├── napkinTests/             # Unit tests... :)
└── napkinUITests/           # UI tests... :)

Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Make your changes following the existing code style
4. Ensure all tests pass
5. Commit your changes (git commit -m 'Add amazing feature')
6. Push to the branch (git push origin feature/amazing-feature)
7. Open a Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments

• Built with Claude Code!

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Note: Napkin is a personal finance calculator, not financial advice. Always consult with qualified financial advisors for important financial decisions.