It enables the user to select any part of the Bodygraph, whether Center or Gate or Channel and choose whether the Gates are Red or Black or both. 

In this way a Channel or Gate can be specifically created as needed, without the need to find any birth data. 

Primarily it is used for creating presentations for slides or illustrations.

It is a highly useful tool for those who wish to teach or demonstrate any particular aspect of the Bodygraph easily and clearly. 

It will work on Windows or Mac or Linux because access is via the browser whatever the operating system, Google, Safari, Firefox etc.