Microsoft is taking the search war with Google to a new battle field, Apple's iPhone and iPod Touch. Announced Tuesday afternoon, Bing for the iPhone [iTunes link] brings many of the functions to the mobile platform. The app's home screen, like Bing.com, has a daily image with clickable hotspots that reveal related trivia. From the app's home screen you can select to display news, maps, movies, images, businesses or directions. And much like Google's iPhone app, the Bing app allows you to do voice search, simply click the microphone icon and just say what you want to search for.