Christmas Shopping App?

[BlackDynamite]

What is a good Christmas shopping app?

Specifically, I am hoping to find something that does the following:

-Enter the total budget for what you intend to spend on everyone combined.
-Automatically calculates how much you have left after buying a gift for someone.
-Lets you enter the amount you intend to spend on each person.
-Lets you share and collaborate your list with other users of the app (so the wife can put it on her phone too and either of us can update it in real time).
-Possibly enter gifts by scanning the barcode.