I have a new app, Mobile VR Station for iOS. Its basically a media player with head tracking and MFI controller support. It can project 2D, 3D SBS or 3D Over Under content onto multiple types of projections. It currently supports Curved, Full Dome, Spherical, Cylinder & Plane projections. Its currently available for download and highly customizable. If you do download it, please check out the help videos, it can get complicated.
Here is a video of myself using the App to view some spherical & panoramic content: http://youtu.be/ssG86L5FQKw