The organise button 
allows you to restructure your categories and sub-categories.
Organise gives you an upper and a lower list with your category structure in each. These lists allow you to view categories and sub-categories in two different parts of your list simultaneously. You can drag a category from either list to the other list to move it from one place to another. If you drop a category on top of an existing category, Phoenix will allow you to merge the two categories together, or insert the new category before the existing one.
You also have the same capability with sub-categories. By dragging a sub-category from one list to the other you can
•Re-order sub-categories within a category.
•Move a sub-category from one category to another category.
•Merge two sub-categories together to form one.
IMPORTANT: BEFORE YOU MERGE CATEGORIES OR SUB-CATEGORIES PERFORM A BACKUP OF YOUR DATA. ONCE CATEGORIES &/OR SUB-CATEGORIES HAVE BEEN MERGED YOU CANNOT UN-MERGE THEM APART FROM MANUALLY ALTERING EACH TRANSACTION OF THE NEWLY MERGED CATEGORY/SUB-CATEGORY.
NOTE: The categories or sub-categories must be the same type to merge. You cannot merge an income category/sub-category with an expense category/sub-category.
