This feature is available on all Goodshuffle Pro Plans.
Let's say you want a category to appear on your invoices that doesn't fit under a traditional line item group or logistics category.
To add this custom category, all you need to do is click 'Add Line Item Group' in your project with whatever category you would like to include on your quotes/ invoices (in this case 'Design').
Now you can add your existing or custom items to this new line item group and just look how nice it looks on a quote!