The sort order of products in the catalogue is managed inside the app. This allows each user to set their own preferred ordering scheme.

You can sort your products alphabetically or numerically. See this article for how to change the sort order: 

How can I change the sort order of products?

Product categories are displayed alphabetically.

For both products and product categories, if you prefer to present them in a manner other than alphabetical, you can place ’01.’ , ’02.’ ,  etc. in front of the product names or product category names to force a specific sort order.