Private Period Sync is a private period and cycle diary for Android. Log how you feel in a few taps, keep history on this phone, and optionally sign in with Google to sync. Invite a partner only if you want — they see the windows you choose, not your full notes.
This app is not a medical device. It does not diagnose, treat, or replace a clinician. Cycle and fertile windows are estimates, labelled as estimates.
WHAT YOU CAN LOG
• Period days and flow (none, spotting, light, medium, heavy)
• Pain (0–5) and mood
• Private notes
• Edit or delete a day anytime (delete asks you to confirm)
TODAY AND HISTORY
• A timeline centered on today
• A cycle strip using your period and cycle length defaults
• History grouped by month — tap a day to change it
• Insights from your own logs (counts and averages). Guidance only.
REMINDERS
• Optional cycle reminders and a nightly check-in
• Optional period facts
• Partner care tips only if sharing is on and they opt in
• Notifications need permission; you can leave them off
PRIVACY ON THIS PHONE
• Logs start in an on-device SQLite database. You can use the app fully offline.
• Optional PIN lock, with fingerprint or biometric unlock when the device supports it
• Optional disguise launcher icon and label (notes, calculator, weather, or calendar) so the home screen does not advertise a period app
• Light, dark, or system theme
GOOGLE SYNC (OPTIONAL)
• Sign in with Google to back up cycles and daily logs to Firebase
• Skip sign-in and stay local-only
• Sign out anytime; logs already on this device stay until you delete them
PARTNER SHARING (OPTIONAL)
• Create an invite and choose what to share: period window, PMS window, fertile estimate, support notes
• Revoke sharing at any time
• Partners see a limited view meant for support, not your private diary
Log periods privately. Offline first. Optional Google sync and partner share.