With iPhone 5 with Safari in landscape mode I have to tap once at top of screen and address bar appears and then I can tap a second time at top of screen to scroll all the way back up to top.
I cannot find a way for even this double tap to work or something else in messages and mail in landscape mode (similar to Safari in landscape in that these apps go full screen in landscape with clock, battery, signal menu disappearing
When put in landscape). When using messages and mail apps I have to rotate back to portrait tap to scroll to top and then rotate to landscape. I submitted bug reports and follow ups when asked, but at some point Apple quit asking if it was fixed even when I updated case saying problem was still there.