Here is some sad news. VLC Player, the popular media player application that can run almost every file format may be removed from the App Store soon. The application made its way in just last week. It is said that this is because the application violates the GNU General Public License that the software is distributed under. These licenses stipulate that any software under GNU must be capable of being copied freely and distributed by the user. But with the Apple App Store, every app is stamped with DRM that makes it impossible for such sharing to take place. In other words, such a GNU-licensed app cannot make it to the App Store.
The copyright infringement complaint in this regard was filed by Rémi Denis-Courmont; an original developer of the VLC player. The iPhone app remains on the App Store as of now. But that can change pretty soon.