A United States Army iPhone application is charging up the Apple download charts. Launched in December, the application has quick become one of the top free news applications in Apple's AppStore.

The application lets users access Army news, images from the Army's official Flickr stream, official Army videos, Army social media sites, podcasts, games and other Army-produced media. Soldiers and loved ones can also use the app to save individual stories, images and videos to a list of favorites and share content via social media and e-mail.

Other features include a key to Army ranks, fact files on Army weapons and units, a look at Army uniforms, audio and text of the Army song, access to back issues of Soldiers Magazine, and the ability to connect to recruiters.

According to the Army, since being released late last month, the application has been downloaded more than 20,000 times, placing it among the top 25 free news applications in the AppStore.

Increasingly, a number of state and local governments, from New York City to Utah, have begun developing applications for the popular mobile device. Utah, for example, has created two iPhone apps that allow residents to access services. One allows users to check the license statuses of various professionals.

However, the Army is one of the first federal government organizations to develop an iPhone application. Among other agencies, NASA has an application that provides users with mission details, photos and video and launch tracking. Some other apps, such as NIC's Most Wanted application (which provides users with information on the FBI's 10 most wanted fugitives) are powered by government data.

Application mobilization tools are both more effective and more confusing than ever. To develop this report, InformationWeek Analytics polled nearly 700 business technology professionals and interviewed mobile application experts. Download the report here (registration required).