I'm having problems with excessive email usage on my iphone 4/ios 7. Just noticed that (settings/usage) it was using 900 mb. I deleted all my mail, deleted the mail account, and it still says it's using 661 mb. My ipad uses a fraction of that.

Question

I'm having problems with excessive email usage on my iphone 4/ios 7. Just noticed that it (settings/usage) was using 900+ mb. I deleted all my mail, deleted the mail account, turned the phone off and back on, downloaded any remaining mail on the server to Outlook on my computer, and it still says it's using 661 mb. My ipad uses a fraction of that.
Background: I recently (December) bought an ipad and set up icloud for contacts and calendar, but NOT mail. My email provider is Verizon. I use computer, iphone, and ipad to check my email; eventually I download it from the server using Outlook on the computer and then delete any remaining emails from the phone and ipad. I can't find info on this problem anywhere.

Answer 1

Howdy there COUGAR444,
It sounds like your iPad all of a sudden seems to be restarting out of no where. If you haven't called AppleCare yet, I would start with quitting either the app that seems to be causing the issue, or all the apps if a single doesn't seem to be the culprit. 
iOS: Force an app to close
Double-click the Home button.
Swipe left or right until you have located the app you wish to close.
Swipe the app up to close it.
When you have done that restart the device and test the issue again:
iOS: Turning off and on (restarting) and resetting
If the issue persists, backup your device to iTunes, then restore it as new and verify that it works. 
How to erase your iOS device and then set it up as a new device or restore it from backups
If it does, then restore your backup to either verify it still works and the software just needed reinstalled, or isolate the issue to the backup file itself. 
Thank you for using Apple Support Communities.
Regards,
Sterling