Several iPad users have noted an issue in which opening Pages or Numbers document from within Mail (as an attachment) results in a situation in which the document cannot be exited, and the user cannot return to the home screen. The only option for getting back to the home screen, in these cases, is to reboot the iPad by holding down the sleep/wake and home buttons.
Note that controls only appear in portrait mode when using these applications; some users report a lack of controls in both portrait and landscape mode.
Apple Discussions poster mitchellriggs writes:
“I emailed a multiple sheet Numbers document to myself and now mail is stuck with the attachment opened, and no way to close it. I have no controls in portrait OR landscape.
Mail is stuck with this attachment open and I cannot get out. I have tried restating Mail but it does not work. I had to restart the entire iPad to get Mail back.”