Video Input

am looking for a device / Software that I can use with my IPAD to view a video that is coming from an external source.

What i have is a monocular night vision - that has a video out.
I need a device that I can hook the video out to a video in. So multiple of us can be watching it without having to look through the view finder.

Even better if it could record by a touch of the button.....

I don't want to spend tones of money, but just wondering what is out there.

I posted in the mac apps forum too. Not trying to duplicate, but I could do this with either but prefer the iPad for ease.