Nothing I tap or touch will bring up and controls or options. The mail app is stuck displaying a PDF from an old message, which was copied to the bookshelf and viewed there (already). Can't seem to tap my way to close the doc in mail, and get on to new mail! Help!

try the home button, if it still doesnt work. reboot your ipad.

How do you reboot? 'reset all settings'? Home button just exits and the app reopens with PDF displayed, no tap menu, over and over.

reboot is turning your ipad off then on.

Also, if that doesn't work.. Open mail so the PDF is showing then hold power and home key until the apple logo comes up. Resets the app itself.

Plenty of people are reporting this bug. Just hold the sleep/wake button and shut down, then restart.

Thanks for the replies - yes, this worked fine and till now had no idea how to reset the pad. Again, thanks!!