One of the nice things about the companion app is that I can use it to manage my armory chest when not logged in. However, this is made difficult by the fact that there's no indication of what items are part of a gearset, and so it's very possible to unwittingly sell items that are currently in use by one of your classes.

It would be nice to have an icon to indicate whether an item is part of a gearset, or a warning if you attempt to sell/discard a gearset item.