Ebb — Private Cycle Tracker

Ebb is a period and cycle tracker built on one promise: your data never leaves your phone.

No account. No sign-up. No ads. No analytics. No cloud. Everything you log is encrypted on your device and stays there — the app's only network use is Google Play Billing for an optional purchase, and it never touches your health information.

Ebb is not a contraceptive and not medical advice. Predictions are estimates and never imply contraceptive reliability.

Predictions, daily logging, the calendar, reminders, encrypted backup, and the app lock (including the decoy PIN) are free and stay free. An optional one-time or subscription purchase unlocks a set of extra tools (BMI, due-date, and kick-counter calculators, and more) — Ebb never paywalls knowing your own body.

WHY EBB IS DIFFERENT

• Truly offline where it matters — there is no server for your cycle data, ever.
• Encrypted at rest — your database is protected with SQLCipher (AES-256) and the Android Keystore.
• App lock — secure the app with a PIN, your fingerprint, or face.
• Decoy PIN — a second PIN opens a genuinely empty version of the app, in case someone forces you to unlock it.
• Honest predictions — Ebb shows a date range, not a fake-confident single day, and tells you when your cycle is too variable to predict. No app actually knows the exact day.
• Encrypted backup you control — export an encrypted .ebb file anywhere you like, protected by a passphrase only you know. Losing your phone doesn't mean losing your history.

TRACK WHAT MATTERS TO YOU

• Flow, symptoms (with severity), mood, intimacy, basal body temperature, and private notes
• Custom symptoms — track anything, not just a fixed list
• A clean calendar and an honest cycle ring on the home screen
• Insights: average cycle and period length with a regularity read, symptom and mood trends, cycle-length history
• A history report by week, month, or year

FOR EVERY STAGE

• Choose your intent: general health, trying to conceive, avoiding pregnancy, or health-only (no fertility framing)
• Pregnancy, postpartum, and perimenopause modes that adapt the whole app
• Fertility signals: BBT and cervical-mucus tracking, folded honestly into predictions

HELPFUL TOOLS (all on-device, nothing stored unless you choose)

• Contraction timer with a shareable log
• Kick counter
• Due-date calculator — from your last period, conception, an ultrasound scan, or an IVF transfer date
• Date forecast calculator
• Doctor-visit summary you can share
• BMI calculator with a healthy-weight range and reference ideal weight
• Cycle-regularity report, BBT ovulation check

REMINDERS THAT RESPECT YOU

• Period, fertile-window, and daily-log reminders at the time you set
• Exact-time medication reminders (pill, ring, patch, injection) with snooze
• Notifications hide their details on the lock screen

IMPORT YOUR HISTORY

• Restore from an encrypted Ebb backup
• Import your period history from Health Connect (read-only — Ebb never writes back)

A NOTE ON HONESTY

Ebb is not a contraceptive and not medical advice. Predictions are estimates and
never imply contraceptive reliability. Ebb describes your cycle; it doesn't
diagnose it.

Your body. Your data. Your phone. That's the whole idea.