Would you please provide more details about the problem so that we can assist you?
Does it appear that Acrobat Reader for iOS is fully updated? Or does it look like the update is "stuck"?
Are you able to launch Acrobat Reader by tapping the red app icon in the iOS home screen?
"the screen goes blank" - Can you explain what happens after it goes blank? Does it take you back to the iOS home screen? Do you see an error message or alert when you re-launch Acrobat Reader?