There are several ways to predict the fertile days. We are going to consider one of the most popular methods which is based on ovulation. To create the fertility tracker, you will need:

• Your period
• The application

The application, in turn, is based on scientific research, which is done by Rodrigo Guerrero, who discovered the fertile days. 

This application determines the fertile days for you and it is based on the scientific theory, which is proven by hundreds of thousands of women. However, some scientific research is not published yet. But we’re planning to update the application as soon as the new scientific findings will be available.