Certain versions of Google Chrome for Windows as well as Android have recently rolled out an updated "New tab" page which has a prominent Google Search box on the page. Google claims they made this change because users were not discovering that they could search from the address bar and still used to go to Google.com to search.
However, if you are not happy with the "Search" text box above the thumbnails of the most visited sites, you might want to disable it. The good old "New tab" feature had some really useful features like recently closed tabs including tabs from other devices. If you are interested in getting those features back, here are simple instructions on how to disable Search on the 'New tab' page in Google Chrome.