Microsoft this week delivered a new mobile version of its Bing search service, and among the offerings was a little surprise for iPhone users: An actual Bing app for the iPhone. This is Microsoft's first mainstream iPhone app—it had previously shipped two beta niche utilities for the device—and is the first of what sources tell me will be a "flood" of iPhone apps from the software giant.

"Today we are happy to announce the first official Bing App for iPhone and iPod touch," a posting to the official Bing Blog reads. "You can now download the free Bing App from your phone in the App Store, from your computer at iTunes, or go to m.bing.com and we will redirect you to the App Store."

Like the normal web-based Bing service, Bing for iPhone features a different high-quality photo every day, with matching notes and annotations and, in the case of the mobile version, a way to search for related imagery online. Bing for iPhone provides both text- and voice-based searching, and can search for web links, news, images, local business, movies, and maps and directions. And as you might expect, it integrates with the iPhone's location functionality to find information that is nearby.

Users of other smartphones can also check out the company's new mobile version of Bing on their device's web browser. The mobile version of Bing includes many of the same features as the iPhone app and adds sports, flight status, and other search types. Users with an iPhone, Zune HD, T-Mobile G1, Verizon Imagio, or Samsung Omnia device will also gain access to an enhanced touch-based interface, Microsoft says.

I've posted a short preview of the Bing for iPhone application on the SuperSite for Windows