Google is revamping GMail and adding new features, including placing the attachment at the top of the email thread, delayed replies (which will enable a user to snooze an email until another time), nudge to reply reminders, and smart replies. Some privacy geeks may be concerned that a machine is reading their Gmail and suggesting replies, but Rich says it's very convenient in the mobile app. Other features include Confidential mode, where the message will self destruct after being read. A new task app in Gmail. And the ability to read emails, tasks, calendar, and notes in one screen.
If you want to enable the new Gmail now, go to GMail, select settings, then "Try New GMail". If you don't like it you can downgrade, but Rich says that eventually, Gmail will require transitioning to the new version.