iPad screen sharing app for 1st gen iPad

[chrisnova777]

is there any app that i can put on my first gen ipad to be able to use it as a second monitor for my computers?

im having trouble finding one that will install on ios 5.1.1 (the os cutoff for the ipad 1)
i need someone with extensive expertise to show me the way!

does anyone know if "air Display 3" app will work to install on ios 5.1.1?
(ie: some apps let u download an older compatible version)