So, in the app you can equip and unequip different items, move them to your vault, and delete them etc.
I think, it would be amazing, if you could buy items from the vendors on the app, and have them when you go in-game.
I keep going to the vendors, and trying to purchase items from them, even though I can't, and most of the time, I feel it's a bit of a waste of time to have to go through the trouble of buying them at the tower. (Love the tower, just saying)
Cheers ;)