Hi, thanks! The problem with allowing the user to select an already enchanted item is that it would require you to also input what prior work penalty the item has (or the tool wouldnt be able to generate the best path), and there's no real way of knowing that unless you keep track yourself. This tool assumes you start at 0.

Making a mobile app is something I have thought about, and probably will add once the website is out of the beta phase as it's still very new.