Have the original model IPad and recently loaded ver. 5.1.1. I was not able to reload Facebook. Tried several times. It shows the icon as if it is downloaded but when I open Facebook I just get a white screen and then exits the program and return to the home screen. Any ideas?
You may just be out of RAM. The memory in the original iPad was quite small. Try this and see if your Facebook account loads....
Double press the round Home button to expose the task/history bar at the bottom. Tap and hold any icon until they all jiggle with a red minus sign in the top left corner. Tap all the minus signs one by one until all apps are closed. You are not deleting them, just forcing them closed. Now tap anywhere above this bar to return to the home screen. Also you might want to clear your browsing history, cookies and data in Safari to free up some more memory.