Yahoo! Shopping

From Yahoo! Inc:

The Yahoo! Shopping application for iPhone and iPod Touch lets you search through and buy from millions of products in our vast catalog anytime, anywhere. Whether youre out with friends, on a bus, or in a store, you can search, compare prices, read reviews, save, share products with others, and click to buy at any one of our merchant Web sites directly within the application.

FEATURES:

Tax and Shipping Calculation - Let us know where you are, and we'll calculate tax and shipping automatically where possible. It's nice to know the total cost!
Ratings & Reviews - Get the skinny on an item from Yahoo! Shopping's extensive database of user ratings and reviews
Shared Products - Want some more advice? Send any product to a friend via e-mail.
Saved Products - On the run? Save a product to your bookmarks list and check out the details later.
Yahoo! Search Assist - When you start typing in your search, we use Yahoo!'s leading search technology to suggest products and save you typing effort.
Search by UPC Type in a UPC code when you search, and for products that have one in our catalog, voil, they appear.