World Organisation of the Scouting Movement published an iOS app during last year's World Jamboree. In the course of the last week, the official Android app has also been released. These apps help you keep up to date with the latest news, pictures and events from WOSM, as well as letting you browse the library of documents.
Both are free, and work on phones and tablets.
iOS app from the App Store
Android app from the Google Play store