This tutorial will guide you through the steps to change your email password on your iPhone.
1. Go to the Settings icon. It may be located on a different screen or in another location than shown here.
2. Select Mail, Contacts, Calendars.
3. Choose the Email Account for which you want to update the password.
4. Select the Email Account you wish to update.
5. Update your email password by entering your New Password.
Note: You should only do this if your email password has changed.
6. Press Done