For those times when a notification sound is not ideal, you can set your phone to vibrate instead whenever you receive email.
1.Tap the Nav Icon at the top left corner of the Nav Bar to display the Navigation Drawer.
2.Tap the Gear icon at the bottom of the Navigation Drawer to bring up Settings.
4.Tap Notifications at the top of the screen.
5.With the notification radio button enabled, tap Vibrate to open a menu of pulses on the phone.
6.Select the pulse for the vibrate notification.