On the FitOS Home page you will see the following sections and icons. 

Profile access, settings, and app management: 

App Cards: 

Circled below in red, these show the Echelon apps available to you. 

Folders: 

Circled in red, the folders contain apps you have downloaded as well as the Weather. 

The apps are split into categorized folders: News, Social, Games, and Entertainment

Folder inside view: 

When you tap a folder it will expand to allow a better view and access to those apps. To exit a folder simply tap outside the folder area.