Clue: Period & Cycle Tracker

Clue: Period & Cycle Tracker, from Clue Period Tracker by BioWink, is a menstrual cycle app that describes itself as women-led, science-based and privacy-first. Beyond predicting the next period, it aims to help users understand hormones and reproductive health at every life stage, from teens to people trying to conceive.

The everyday view is a period calendar that shows when the next period is expected, and Clue doubles as an ovulation calculator for following fertile days. Users can record more than 200 factors, among them mood, sleep, energy and libido, and watch how each changes over the cycle while spotting patterns in regularity and flow. Reminders cover birth control pills and upcoming periods, and alerts mark the start of each new cycle phase. There are modes for fertility tracking and pregnancy, and more than 300 expert-written guides on cycles, fertility and pregnancy sit inside the app. The developer highlights that data is handled under strict EU privacy law.

It has 50,000,000+ installs and a 4.5 average from almost 1.5 million ratings; 75% are five stars and 5% are one star. The app has no ads, but in-app purchases range from $0.99 to $74.99 per item, pointing to paid tiers on top of the free tracker. It was updated on 2026-09-17, is rated Everyone and needs Android 8.0 or newer. We list 34 versions; the latest, 270.0, is 53.3 MB.

Anyone who wants detailed cycle tracking with plenty of educational material and an ad-free interface will find it a strong fit. Those who only need a basic period calendar may not need its depth or paid extras.