From the Home screen, tap the Google folder > Gmail > Menu Key .
Tap Settings.
Tap General settings to change the following settings for all accounts.
Archive & delete actions: Sets if you want to display only the archive option, only the delete option, or both options.
Swipe to archive: Checkmark to archive a conversation when you swipe it.
Sender image: Checkmark to display the sender’s image next to the name in the conversation list.
Reply all: Checkmark to make Reply all the default message action.
Auto-fit messages: Checkmark to shrink the messages to fit the screen and allow zooming.
Auto-advance: Sets which conversation list is viewed after archive or deletion.
Message actions: Sets when to show the action icons on the message header.
Confirm before deleting: Checkmark to ask to confirm before deleting a message.
Confirm before archiving: Checkmark ask to confirm before archiving a message.
Confirm before sending: Checkmark to ask to confirm before sending a message.