Your profile picture is the best way to identify you.
To have a Developer Application appear on your list, you must participate in the application and have the application save its state.
Each Developer Application has a different requirement of saving your state. Some requires you to save your progress, while others will automatically save your state on during the first time you run the Developer Application.
You cannot remove a Developer Application from your list. Once it is listed, it will always appear in your list.