Get the best Ovulation and Pregnancy Calendar now! OP Calendar predicts your fertility window by tracking your periods so that you can plan ahead for pregnancy. Use your fertile or less fertile days to your advantage, and take the guesswork out of family planning.KEY FEATURES:1.Easy to understand user interface2.Accurately predict your future periods and fertility windows3.Keep track of your last fun encounter4.Predict your due date if a baby was conceived5.Custom color choices for high and low fertility days6.Optional passcode to protect your privacyThe interface is simple to understand and custom color-coded. High fertility days can be shown as green and low fertility days can be shown as red, or vice versa, depending on what is most intuitive to you. This feature is very unique, as other apps have non-custom colors that can be confusing.Upon inputting the beginning and end of your menstrual cycle, the app does all the complicated calculations for you so you know which days of the month you can let loose and have unprotected fun and which days to avoid. The app also incorporates the latest gender prediction theories to let you know which days may result in the conception of a boy or girl.CAUTION:Menstrual periods and ovulation cycles vary from woman to woman and month to month. This tool should be used as an estimate only and not as a replacement for professional medical advice.