This particular application was released this past August 17th by Anchoright Productions in association with Christ the King Catholic Church in Sarasota, Florida -- an FSSP parish.
The application is described as follows on the iTunes App Store:
iMass makes it possible to view Holy Mass each day directly on your iPhone.
Whether you are at the park, on a bus, at a coffee shop or in the comfort of your home, you can view Holy Mass and unite your prayers to it.
The Mass is celebrated in the Extraordinary Form by the Priestly Fraternity of St. Peter at Christ the King Catholic Church in Sarasota, Florida, USA.
The app also provides the text of the Mass of the day according to the 1962 Missal, making it useful as a missal for the participation at Mass.
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Version 1.1 update (coming soon) will have the landscape view of the Mass video.
Here are some screenshots from the iMass application:
The application is available from the iTunes store for $1.99 USD and requires iOS4.