Privacy-First Period Tracker
Your reproductive health data should never become a liability.
Ebb is a privacy-first menstrual cycle tracker designed so that your most sensitive health data never leaves your device.
Unlike traditional period tracking apps, Ebb follows a zero-knowledge architecture where even the developers cannot access user data.
Most period tracker apps collect and store fertility data on centralized servers.
This creates serious risks:
• Data can be sold to advertisers.
• Data can be subpoenaed by authorities.
• Databases can be breached.
• Personal health data can be exploited.
Ebb solves this by removing the server entirely.
All data remains encrypted and stored locally on the user's device.
Ebb is built around a strict privacy model.
Key principles:
• Client-side encryption.
• No cloud storage.
• No analytics tracking.
• No user accounts.
• No advertising SDKs.
• No telemetry.
Because the data never leaves the device, no company can access it.
• AES-256 encryption.
• PBKDF2 key derivation.
• Local encrypted storage.
• Offline-first architecture.
• Zero-knowledge design.
This means:
✔ We cannot read your data.
✔ We cannot sell your data.
✔ We cannot give it to anyone.
Because we never receive it.
Current features:
• Period tracking.
• Cycle history.
• Symptom logging.
• Mood tracking.
• Offline functionality.
• Encrypted local storage.
Planned features:
• Private cycle predictions.
• Encrypted backup export.
• Advanced symptom tracking.
• Privacy-safe analytics.
Clone the repository:
git clone https://github.com/lyfmail-official/ebb.git
Navigate to the project:
cd ebb/app
Open the app:
index.html
No server is required.
Ebb runs entirely in the browser.
📂 Project Structure
```bash
ebb
│
├── app
│ ├── index.html
│ ├── manifest.json
│ ├── service-worker.js
│ │
│ ├── css
│ │ └── app.css
│ │
│ ├── js
│ │ ├── app.js
│ │ ├── crypto.js
│ │ ├── storage.js
│ │ ├── cycle.js
│ │ └── utils.js
│
├── docs
│ ├── encryption.md
│ ├── threat-model.md
│ └── architecture-diagram.md
│
├── LICENSE
├── README.md
├── SECURITY.md
├── PRIVACY.md
├── CONTRIBUTING.md
└── CODE_OF_CONDUCT.md🔍 Threat Model
Ebb was designed to mitigate:
• Data broker surveillance. • Government subpoenas. • Database leaks. • Advertising tracking. • Corporate data exploitation.
Mitigation strategy:
• No central database. • Local encrypted storage. • Open source transparency.
🌍 Open Source Philosophy
Ebb is fully open source so that:
• Security researchers can audit the code. • Users can verify privacy claims. • Developers can contribute improvements. • The community can build trust.
Transparency is essential for privacy-critical software.
🤝 Contributing
We welcome contributions from developers, designers, and security researchers.
To contribute:
Fork the repository. Create a feature branch. Submit a pull request.
Areas where help is valuable:
• Cryptography auditing. • Privacy architecture. • UI/UX improvements. • Accessibility improvements. • Security reviews.
See CONTRIBUTING.md for details.
🛡 Security
If you discover a security vulnerability, please report it responsibly.
Contact:
Please do not open public issues for security vulnerabilities.
📜 License
This project is licensed under the GNU Affero General Public License v3.0 (AGPL-3.0).
This ensures that:
• The software always remains open source. • Improvements must remain open. • Privacy protections cannot be removed in closed forks.
See the LICENSE file for details.
❤️ A Note on Privacy
Reproductive health data is among the most personal data a person has.
Ebb exists to ensure that technology protects users instead of exposing them.
Your body. Your data. Your control.
🌊 Official Website
Learn more about the project:
⭐ Support the Project
If you believe privacy-first health technology is important:
⭐ Star the repository. 🔁 Share the project. 👩💻 Contribute improvements.
Together we can build ethical FemTech.
Maintained by LYF Mail · Founded by Ajay Kumar Chaudhary