Phasa: Period Tracker Calendar

Most period apps hand you one confident date. Bodies don't work that way. Phasa shows the days your period is likely to start, and that range tightens as it learns your rhythm — or stays wide, honestly, when your cycle is irregular.

HOW PHASA READS YOUR CYCLE • Looks at your recent cycles, sets aside the odd month out, and leans on the most recent ones • Shows a prediction window plus a confidence level that says what it's based on • Log basal body temperature and Phasa looks for the sustained rise after ovulation, then learns the length of your own luteal phase instead of assuming 14 days • Fertile window and phase for every day of your cycle

PATTERNS WITH THE EVIDENCE ATTACHED When Phasa spots something in your logs — headaches clustering before your period, low energy after short sleep — it tells you how many cycles that observation rests on. You decide how much it means.

LOG IN SECONDS Flow, symptoms, mood, energy, sleep, temperature, cervical mucus, notes and photos. A calendar that shows logged days, predicted periods and your fertile window at a glance.

MADE FOR DIFFERENT SEASONS OF LIFE Choose Period Tracking, Trying to Conceive, Pregnancy (week count, trimester and an estimated due date) or Perimenopause, where predictions widen to fit shifting and skipped cycles.

PRIVATE BY DESIGN • No account and no sign-up • No server, no analytics, no ad code — your logs stay on your iPhone • Face ID / passcode lock and discreet reminders • Export everything as a file, or delete everything permanently, in one tap

WORKS WITH YOUR IPHONE Two-way Apple Health sync, home-screen widgets, and a PDF summary you can take to an appointment.

FREE AND PHASA PLUS Logging, the calendar, predictions, Apple Health sync, export and deletion are free. Phasa Plus adds deeper pattern analysis, your full charted history, PDF reports, partner sharing and custom symptoms.

Phasa Plus: weekly ($3.99, 3-day free trial for eligible new subscribers), monthly ($9.99) or yearly ($29.99), or your local equivalent. Payment is charged to your Apple ID. Subscriptions renew automatically unless cancelled at least 24 hours before the end of the current period; manage them in your Apple ID settings.

Terms of Use: https://phasa-app.web.app/terms.html Privacy Policy: https://phasa-app.web.app/privacy.html

Phasa is an information tool, not medical advice, and it is not a contraceptive.

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