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CLUSTER PERIOD-DATA-OVULATION · 20 ENTRIES · EARLIEST ENTRY 2015-06-28

Privacy-first period trackers

This cluster consists of period and fertility tracking apps that prioritize privacy through on-device storage, no accounts, no ads, and no cloud sync. Their dated history shows single entries in 2015 and 2018, followed by seven entries between July 2025 and July 2026, indicating a recent concentration of development. Traction leaders include Clover – Period Tracker, Cycle, Period Tracker: Bloom Cycle, and Lulu - Best Period Tracker, all currently with zero stars.

Entry timeline

ENTRY TIMELINE

JUN 2015: 1APR 2018: 1AUG 2018: 1JUL 2025: 1NOV 2025: 1JAN 2026: 1FEB 2026: 1MAR 2026: 1APR 2026: 2MAY 2026: 1JUN 2026: 3JUL 2026: 3AUG 2026: 2SEP 2026: 1
JUN 2015SEP 2026

Each bar is the month a member carries, which is a creation date where the source published one and a crawl date otherwise. Nothing in the index was found before 11 August 2026, and coverage broadened sharply on 14–15 August, so a bar from then on reports how much we found that month, not how much was built; an earlier bar reports how far back a member's own source dated it — not how long we have been watching.

Members by activity

Activity signals, not revenue.

Build origin · 20 unlabelled

Operator · 3 hobby · 3 commercial · 1 open source · 13 unlabelled

Two labels per entry, never collapsed into one: how it was built, and who stands behind it. Counted over the 20 listed below. Unlabelled means nothing has decided yet — not that the answer is small.

  1. 01Clover －Period Tracker, Cycle0★11 dayslivecommercialPeriod tracking app that keeps cycle data on-device without an account, offering calendars, ovulation predictions, and reminders for women.
  2. 02Peri: Period Tracker0★5 dayslivehobbyOffline period tracker that logs cycles manually, predicts periods, shows a calendar, sends reminders, and exports history without requiring an account.
  3. 03Period Tracker: Irregular0★24 dayslivePeriod tracker that predicts next period and fertile window from on-device history, with no account, cloud, or ads.
  4. 04Niah: Private Period Tracker0★25 dayslivePeriod tracker that logs periods, symptoms, and fertility signs and predicts next periods and fertile windows without sending data to servers.
  5. 05Lulu - Best Period Tracker0★1 moliveAd-free period tracker that predicts cycles and ovulation with pregnancy mode and emphasis on privacy.
  6. 06Period Tracker: Private Diary0★8 dayslivePeriod tracker that logs cycle days and symptoms privately on-device, predicts next period, and exports history for clinicians without requiring an account.
  7. 07Period Calendar & Cycle0★1 molivePeriod calendar app that predicts next period, fertile window, and ovulation from logged health data without ads or accounts.
  8. 08Offline Period Tracker: Enria0★1 moliveOffline period tracker for iPhone that logs cycles, symptoms, and temperature, predicts fertility windows, and syncs with Apple Health without requiring an account.
  9. 09Period Tracker Symptom & Mood0★1 molivehobbyPeriod tracking app that logs cycle, symptoms, mood, and predicts periods and fertility without an account or data sharing.
  10. 10projectx_ai0★1 mo—hobbyShared calendar that helps groups track menstrual periods, with access limited to authenticated users.
  11. 11Period Tracker: Cycle & Mood0★2 molivePrivate period tracker that records flow, mood, and symptoms with device-encrypted storage, no ads, and no cloud backup.
  12. 12Cylla: Private Period Tracker0★2 molivePrivate period tracking mobile app that logs cycles, symptoms, and fertility data entirely on-device without an account or cloud storage.
  13. 13Period Tracker - Adet Takvimi0★2 molivecommercialOffline mobile app that tracks menstrual cycles, symptoms, and fertility with encrypted local storage and no account.
  14. 14Period Tracker: Private Log0★3 molivePrivate period tracking app that logs cycles, symptoms, and moods with on-device encryption, offers predictions and insights, and requires no account or cloud.
  15. 15Fertility & Period Tracker •0★2 yrabandonedlivecommercialFertility and period tracker app that predicts ovulation and period dates, logs health data, and works without an account.
  16. 16BoB0★11 daysliveopen sourcePrivacy-focused pregnancy tracking app that requires no permissions.
  17. 17HerFlow: Period Tracker0★4 moliveMinimalist period tracker that stores all data locally on device, requires no account, and offers a single-screen calendar view for cycle tracking.
  18. 18ULA Period Tracker0★6 mostalelivePrivacy-focused period tracker that logs symptoms and predicts periods, ovulation, and fertile windows entirely offline on the device.
  19. 19Private Period Tracker0★8 mostalelivePeriod tracking app that keeps menstrual health data locally on the device, predicts cycles, and works without an account or data sharing.
  20. 20Flowcast Period Tracker0★11 mostalelivePrivate period tracker app that allows multiple people to follow each other's cycles with no server storage or accounts.

Ranked by traction, highest first, and paged 20 at a time — this is a window on the cluster, never the whole of it. Ties are broken by a stable id so a product cannot appear on two pages or fall between them. Browse every cluster.