With loaner and shared ipad use growing in our schools we start to find new issues. One that i have come across is with the use of khan academy (this will work for both the Khan Academy app and Safari on ipads) and the login screen, Khan academy uses our students google login to utilize their site and when the user is in a hurry or dose not read all the message pop ups iw will cache their credentials without the option to alter it. upon working with staff in the classroom i have been able to make a quick sure fire way to clean this up for a new user.
Navigate to SETTINGS, on the left hand side scroll down to SAFARI and tap on it, once the safari tab loads on the right you will need to scroll to the bottom, tap on ADVANCED, then tap on WEBSITE DATA. here you can see all the cached web info. at the bottom you should see REMOVE ALL WEBSITE DATA, once you tap this you will get a warning making sure that is what you want to do, tap REMOVE and that's it. No need to reboot the device or exit out of the app, it is all done in real time. PICS below for reference, I am sure as the programs grow they will be able to include chrome and other browsers which I am sure will still have the same issue for shared devices, but the process should be similar.