With the availability of tablet devices, I was asked to build a VoD application for tablets, which I did using C++ and Marmalade for extra-interactivity and smoothness.
This was supposed to be used in a normal VoD context, but also in an unidirectional context (when there’s no return path on the STB), so the customer would order a movie to watch on his tablet and then watch it on the TV on a standard cable network.
This would configure a multiplexer on the fly and setup a TV channel for the movie, along with the scrambling necessary to grant the user rights to watch the movie.
The network costs were too high, though, and although the project technically worked, it never got implemented on the field.
In this case, I developed the whole solution myself, using C++ and ObjectiveC, with some OpenGL on the frontend, and C++ on the backend using a modified OpenSource RTSP server modified to stream over a multicast for a video network.