Mongolian Cyrillic keyboard for iOS 5.x.
It will work on iPad which has iOS 5.x firmware. (Tested on iPad2 iOS 5.0.1).
After installing this tweak add Mongolian keyboard by going to Setting > General > Keyboard > International Keyboards > Add new keyboard > choose Mongolian
No icons are added to the homescreen, and there are no options to configure.
See larger Screenshots below