Period Tracker - Menstruation is a free Android application developed by Wako Development, designed to help women accurately predict their menstrual cycle. The app requires users to answer three simple questions: the length of their physiological cycle, the length of their menstrual period, and the date of their latest menstrual start.

Once the user answers these questions, Period Tracker - Menstruation provides them with essential data such as the date of their next menstruation, the date of their next ovulation, and probability of getting pregnant. Users can also set notifications according to their preferences.

It is worth noting that the app is not intended to replace medical advice. Therefore, users should not use it as a contraceptive, but rather consult a medical professional for any medical advice about menstruation, ovulation or getting pregnant.

Overall, Period Tracker - Menstruation is an excellent application for women who want to keep track of their menstrual cycle. It is user-friendly, accurate, and free of charge.