Crowdfunding gifting iPhone app

The basis for the app is that on birthdays or holidays individuals may receive gifts from several sources - parents, siblings, friends, grandparents, etc. Suppose the recipient really wants something expensive. Collectively all the people who are getting her gifts may be able to afford that item, but individually none of them can. This is a case where it would be nice if everyone could pool their money to get their most-preferred gift. Unfortunately, this is not usually acceptable because people do not want to reveal to each other how much they are spending on gifts. This is where the app can facilitate the exchange. I imagine the interface as follows. The recipient can create a wishlist and link to products; the list automatically sorts itself by price. The recipient can also rank each item's importance and share the list with others to view. Givers can enter a budget and credit card information into the app; this is visible only to them. At a date specified by the recipient, the app tallies the total budget of all the givers associated with a particular recipient and computes the best bundle of goods (according to the recipient's rankings) that the group can afford (somehow taxes and shipping costs need to be accounted for here). The app then charges everyone's credit cards the required amount up to their stated budget. This creates a cash pool to purchase gifts from. The recipient will choose a designated shopper from among their givers and this person will receive the list of items to purchase. All other givers can see the list of items that will be purchased. This is a particularly good application for big events - wedding registries, retirement parties, graduations, Bar Mitzvah's, etc.