* Period Tracker 3D - calendar of menstruations. * Two kinds of the calendar - the week begins from Sunday / Monday (selector S/M). * Keeps history of menstrual cycles. * You can add a note to each cycle. * The application will make the forecast monthly for a year using a method of 'weight factors'. * When setting the cycle start date a selector activates to set the duration of menstruation (1 - 10 days). * Convenient schedule of cycle times. * All your data is saved in simple text file - therefore you can securely store it in any place. * Mark days of the beginning monthly. * More marks - more accurate the forecast is. * Choose a calendar day of the month, set selector to position 'START'. The program automatically draws red daisies (during menstruation). * After the second mark, the program starts automatically calculating the estimated days of menstruation and marking them with white daisies. * The calendar will calculate your average menstrual cycle and day of a cycle.