Meridian: Period Tracker

Meridian is a period tracker that stays on your phone. Log the first and last bleed. The forecast then maps the rest of the cycle: period, fertile window, ovulation, late luteal, and the days desire is more likely. Choose what the home number is counting toward — period, pregnancy timing, ovulation, late luteal, libido, or an overview of whichever window is next. There is no account. There are no ads. The app does not use the internet. Cycle logs live in private storage on this device. Android backup is off. Erase all data from Settings if you want the phone empty. What you can do • Mark period start and end • Log sex, libido, tension, anxiety, anger, and hot flashes • See a calendar with period, fertile, and late-luteal tracks • Get optional reminders for the windows you care about • Teach the forecast from real cycles, including irregular and changing ones How the forecast is counted Period start is the only hard date. Ovulation is counted back from the next period using a typical luteal length, then refined from your logs. The useful fertile window is the five days up to ovulation, not the day after. Late luteal is the last stretch before bleeding, when mood is more likely to shorten. Meridian is not a medical device and does not diagnose, treat, cure, or prevent any medical condition. Forecasts are estimates. They are not contraception and not a fertility treatment.