Periodical
Periodical Summary
Periodical is a Android app in the Health And Fitness category, developed by Arno Welzel. First released 13 years ago(Apr 2012), the app has accumulated 23.3K+ total installs and 154 ratings with a 4.80★ (excellent) average rating.
Recent activity: 65 installs this week (296 over 4 weeks) showing steady growth , and 3.00 new ratings this week View trends →
Store info: Last updated on Google Play on Nov 17, 2025 .
4.8★
Ratings: 154
Screenshots
App Description
A menstrual calender with calculation of fertile days according to Knaus-Ogino.
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.