Productivity · Open source
Periodical
A menstrual calender with calculation of fertile days according to Knaus-Ogino.
Opens the official F-Droid page
About Periodical
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.
How to install Periodical
- Tap Download — the app's official page on F-Droid opens.
- Install it with the F-Droid app (recommended, for automatic updates), or use the download button on that page.
- If Android asks, allow the F-Droid app or your browser to install apps, then tap Install.
- Open Periodical from your app drawer.





