This application calculates the fertile days according to Knaus-Ogino and can track menstrual symptoms. WARNING: It is not recommended to use this calendar to avoid pregnancy! There are more accurate methods, like measuring the basal body temperature. The data can be backed up on a memory card or "internal" memory, if present. If you have any further questions or want to help me with translations in other languages, please contact me via e-mail - thank you. This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. You can obtain the source on my website.