From Google blog:
As of today, if you go to Google.com on your iPhone or Android-powered device and search for an app, we’ll show special links and content at the top of the search results. You can tap these links to go directly to the app’s Android Market or iPhone App Store page. You can also get a quick look at some of the app’s basic details including the price, rating, and publisher. These results will appear when your search pertains to a mobile application and relevant, well-rated apps are found. For example, try searching for download shazam on your Android-powered device or bank of america app on your iPhone.