The Kindle app from Amazon got a pretty good facelift today. The iPhone and iPad version is receiving several new features, including a 250,000 entry dictionary and the ability to look up words on Google or Wikipedia. The dictionary, which other apps like iBooks and Barnes and Nobles's ereader already support, allows you to tap any word on the page to get a definition. The update also allows searching within books on the iPad and adds support for fast app switching on iOS 4 devices. The app is free and available for anyone running iOS 3.0 or later.