
Locklune
Private Period & Cycle Tracker
0 ratings
Free
About
Locklune tracks your period and cycle entirely on your device - encrypted, offline, always private.
There is no account to create. No server ever receives your data. No analytics, no ads, no tracking. Everything you log is protected by AES-256 encryption tied to your PIN and never leaves your phone.
WHY LOCKLUNE?
Most period apps upload your most intimate health data to the cloud. Locklune doesn't. It can't - the app has no network access at all. Your cycle history, symptoms, moods, and predictions are encrypted the moment you enter your PIN.
FEATURES
• Period & cycle tracking — log when your period starts and ends, with flow intensity for each day
• Smart predictions — Locklune learns your personal cycle length and improves its estimates as you log more cycles
• Fertile window & ovulation — see your estimated fertile days and ovulation date at a glance
• Cycle phases — know which phase you're in today: menstrual, follicular, ovulatory, or luteal
• Symptom & mood logging — record how you feel each day and spot patterns over time
• Calendar view — see past periods, predictions, fertile days, and logged entries in one place
• Insights — average cycle length, period length, variation, a cycle chart, and upcoming period dates months ahead
• Tomorrow preview — see what to expect the next day based on your own history
• Optional reminders — local, on-device notifications for your period and fertile window (no internet needed)
FIVE MODES
Cycle tracking — full period and fertility view
Period tracking only — periods logged; fertility content hidden
Trying to conceive — fertile window and ovulation front and centre
Contraception — tracks bleeds; fertility details hidden for hormonal method users
Pregnant — switches to a pregnancy progress view showing week, trimester, and days to your due date
PRIVACY BY DESIGN
Locklune's privacy is structural. The app contains no networking code. There is no "sync" to disable. No third-party SDKs that phone home. The database is encrypted with SQLCipher using a key derived solely from your PIN. Without your PIN, the data is unreadable, even to us. There is no account recovery - by design. No background network activity. Works indefinitely without an internet connection.
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Locklune is built for anyone who wants to understand their body without trading their privacy to do it.
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What's New in Locklune
1.0
August 9, 2026



