VLC Streamer uses VLC to handle the actual conversion of movies to the format for the iPhone/iPad.
If you are using an old version of Mac OS (Mac OS 10.5, or Mac OS 10.6 on a 32bit CPU), then please use version 3.50
The linux version is unsupported. It was provided by a generous community member. More info here.
The A version is based on the current VLC. It is best for most filetypes.
The B version is based on an old version of VLC from just before version 2.00.Some users find that it works better for MKV files.