There are several applications (also called "APPS" that you can choose to have on your profile page.

To see the list of APPS that you can add to your profile, go to Application --> Browse

To edit it, go to Application --> Edit. Here, you will be able to:

1. find out what are each APP does

2. Set each APP based on your preferences

3. Set the arrangement of APPs by dragging it (ctrl + drag up or down).

4. Adjust the privacy setting of each APP

5. remove an APP that you do not want to use