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.