Cycle Sister

Track your period, ovulation, and fertile windows with complete privacy.

Cycle Sister is a private, local-first period and fertility tracker. Log your period cycles, track predictions for next cycle, fertile window, ovulation day, and safe windows. All data is kept 100% secure and stored locally on your device.

Key features include: • Period start and length logging • Predictions for next periods and ovulation days • Color-differentiated safe/ovulation/predicted periods • Multi-profile support for recording multiple people (Pro features) • Local backup and restore with strong password encryption

Privacy Policy: https://sites.google.com/view/cycle-care-app/privacy Terms of Use: https://sites.google.com/view/cycle-care-app/terms