We went a little over "multi-screen" support in a previous blog about responsive design, when a web page "responds" to device screen size and automatically alters it's layout and appearance.
However, when it comes to video, things get a little more complicated.
Many of the videos even on YouTube cannot be played on smartphones due to the resolution and size of the video.
Thus, in order to go around this, many devs resize their videos and apps to accommodate multiple screens.
In other words, for "multi-screen" support, you simply have different versions that are used for different screen sizes.
So what is "N-screen" support?
Taking you back to basic algebra, the "N" here is a variable for an unknown value.
In other words, you are supporting all screen sizes without a defined size to support.
This happens through transcoding, in which one source will be automatically re-coded and optimized for not only the detected screen size, but network speed and screen resolution.
Now I would say that's a HUGE difference.
With the various smartphone sizes and tablets, not to mention smart TV and soon to be HTML5 car navigation in the works, N-screen support will become a must when choosing your SDK.
Just imagine creating an animated ad or even a video ad that could be play across all devices without having to alter it manually for specific screen types.
Now that's efficiency.