Google Product Search is now available the UK and the USA in an optimised version for Android and iPhones.
Google software engineer Rob Stacey, who developed the application, explains how it works on the Google Mobile blog
Say you're in a store and having a hard time deciding between two products. Instead of waiting to go home to check the internet for ratings and reviews, you can now get all of this information right there on the spot. Just take out your phone, go to Google.com in your browser, and try out Google Product Search for mobile. From Google.com, type in a query and then tap on the "shopping" link that appears in the search results. Or, tap on the "more" tab and then "shopping" to get to Product Search directly.
Google Product Search for mobile gives you the same product information that you would get at your computer. And when you click on products like electronics and video games, you'll see dedicated product pages that include ratings charts and technical specifications.