This tutorial is only applicable if you are using phpFox version 4.6.0 or later. You can download the latest PHOTOS app for free at https://store.phpfox.com/product/1887/photos

Considering you're already logged in the AdminCP. Go to Apps >> Installed >> Photos

ADDING A CATEGORY

ENABLE or DISABLE a Category

EDIT or DELETE a Category

USERGROUP SETTINGS: In Photos, you can modify the permission for each UserGroups. 

SETTINGS