National Sept. 11 museum launches mobile app

The National Sept. 11 Memorial and Museum has launched the "Explore 9/11" mobile application for the iPhone and iPad.

The application, available free at the online iTunes store, offers a walking tour of lower Manhattan in the area around the World Trade Center, along with photos and audio narration of the events of Sept. 11, 2001.

In addition, the application offers an interactive timeline and photographs of the attacks and their aftermath contributed by survivors and witnesses via 911history.org.

Photos can be viewed in augmented reality mode, which overlays images on the camera view.

Aside from the walking tour, all content is available in off-line mode. “The app can operate in an off-line mode for non-U.S. visitors who have disabled data roaming,” the iTunes description states. "In this mode, all tour content is still accessible. The app includes a map of free Wi-Fi hot spots near the tour route for downloading 'Explore' photos from the vicinity."