http://www.droid-life.com - Here is a full 11 minute tour of Google's new email app called Inbox by Gmail.
Google's new Inbox by Gmail app tour!
Inbox by Gmail Quick Look
Gmail Tutorial 2014 - Quick Start
3 Gmail Add-Ons You Need to Use!
Personalizing Gmail for the Way You Work
The Inbox that works for you
13 Amazing Gmail Tips
How to Create a Gmail Account 2014