Turn Off Push Mail
Most people use text messaging for instant messaging and alerts. Therefore most people don't need a constant connection with their mail server. Plus whenever a user opens Mail, a connection is established to the server and mail is received.
To stop you Apple iPhone from continuously checking the email server to see if the server has new mail, users can tell the iPhone to check every 15, 30 or 60 minutes. That means the Apple iPhone will fetch the mail in one of those time intervals.
If you ever are in a position where you need to hear an incoming email immediately, you can always turn PUSH back on.
Go to Settings -> Mail, Contacts, Calendars -> Fetch New Data
Right under your list of Mail Accounts, you will see "Fetch New Data" ... It will be configured to PUSH or FETCH. If it says PUSH, the user's phone is using a lot of battery power.
Touch PUSH >
Scroll to the bottom and choose Every 15, 30 Minutes or Hourly under Fetch.
If necessary for each individual email account that may be configured to FETCH, tap on each individual email account and, if possible, change it to FETCH. Each individual email account will pickup the FETCH interval specified above.
For example, AOL stayed on PUSH when the main FETCH was configured. It can be changed to FETCH individually.
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