A free program for Android, by Krystian Kamiński.

LadysCalendar is a period tracker that also provides the possibility to track your basal body temperature. This will help you to predict ovulation and fertility days. It has a simple and intuitive user interface. You can easily track the menstrual cycle. It allows you to set the length of the menstrual cycle and the length of the luteal phase. You can also add an end date for the luteal phase. You can also set your basal body temperature.

You can see your current conditions on the main screen. The menu allows you to change the settings. You can also add an icon for the current day.