get rid of duplicate items in multiple categories
Suppose I'm hiking and going to the beach, and I've put "water bottle" in both categories. It would be useful if the app recognized that I don't need two water bottles. So that water bottle is only listed once, even though I've told the app that I'm both hiking and going to the beach on my trip...
Taylor Peterson commented
+1 This is a huge deal for me and is a key differentiator at the moment since none of the packing apps have this feature.