Catalogs manager lets you easily manage catalogs you work on (surprise...). It provides quick and convenient access to your PO files from one centralized place.
Catalogs are grouped by projects. A project consists of its name and set of directories where its catalogs are stored. List of existing projects is on the right side of manager window, files contained in active project are on the left side. Files list contains summary of translated, fuzzy and untranslated strings together with last modification date and a semaphore icon indicating status of the catalog (green = ok, red = (almost) untranslated, yellow = partially translated).
There are four icons in the toolbar - first of them is used to create new project, second for modifying existing project and the 3rd one to delete project.
Finally, the "wheel" icon in the toolbar is used to start mass update of all catalogs in the project. Mass update is same as single catalog update, except for two things: first, it updates all catalogs and second, it doesn't use automatic translation memory.