RhythmWise is not a medical device and does not diagnose, treat, cure, or prevent any medical condition. Always consult a qualified healthcare provider for medical advice, diagnosis, or treatment. Cycle predictions and insights are estimates based on the data you enter and may not be accurate. Do not rely on this app for contraception, fertility planning, or diagnosing any health concern.

RhythmWise is a privacy-first menstrual cycle tracker that keeps all of your data on your device, encrypted and under your control. There is no cloud sync and no internet connection is required.

Key Features:

- Period Tracking: Log period start and end dates, flow intensity, color, and consistency. View your cycle history on an interactive calendar.

- Daily Wellness Log: Record mood, energy, and more each day. Add freeform notes and custom tags to capture anything that matters to you.

- Symptom Tracking: Choose from a curated symptom library, or add your own. Symptoms are organized by category (physical, emotional, digestive, and more). Rate severity and track patterns over time.

- Medication Log: Track medications and supplements with dosage notes. Maintain a personal medication library for quick daily logging.

- Water Intake: Set a daily hydration goal and log glasses throughout the day with a single tap.

- Cycle Insights: View cycle length trends, predicted next period and fertile window estimates, symptom recurrence patterns, mood analysis, and phase-based symptom breakdowns; all calculated locally from your own data.

- Educational Content: Read articles on cycle basics, common symptoms, wellness tips, and when to see a doctor. Content is sourced from U.S. government public health agencies.

- Reminders: Set customizable daily reminders for logging, period predictions, and hydration goals.

- Onboarding Tutorial: Guided tooltips help you learn the app on your first visit without getting in the way later.

Privacy and Security:

- Zero internet permissions: the app cannot connect to the internet.
- No analytics, no telemetry, and no third-party SDKs that transmit data.
- Your database is encrypted with AES-256-GCM via SQLCipher.
- Your passphrase is processed through Argon2id key derivation and is never stored in plain text.
- The encryption key exists only in memory while you are logged in and is destroyed when you lock the app.
- No passphrase recovery by design; only you can access your data.
- Delete all data at any time from Settings.

RhythmWise is free, open-source (Apache 2.0), and contains no ads or in-app purchases.