This info helps if you're looking to modify the amount of data used by your personal email account.
From a Home screen, navigate: Apps icon > Email.
From an Inbox, tap the Menu icon (located in the lower left).
Tap Settings.
If applicable, tap the desired email account on the left.
Tap More settings (located at the bottom).
From the Common settings section edit any of the following: The available settings may vary depending upon the email account type. Enabled when a check mark is present.