- Personal Pickup: Buy in the app and choose to pick up your order at any Apple Retail Store. Most in-stock orders are available for pickup within an hour. (U.S. only)
- EasyPay: Purchase select accessories in store quickly by scanning the barcode and completing your transaction right in the app. (U.S. only, requires iPhone 4 or iPhone 4S)
- Track your stuff: View the status of current and previous orders from the order status section in the More tab.
Apple Store Link
Even you can also buy Apple accessories in the store by scanning the item barcode, making the purchase using a credit card and associated with an iTunes account, and walking out.
This is a great and interesting update by Apple.