Inbox by Gmail: Unified Inbox

Looks like the team is still moving Inbox forward. They snuck a new feature in right under our noses.
There is not much functionality specifically, but this is a big deal for many people as this has been a huge request for some time.

Its clearly indicate at the top of the image to the left. You can see all of your accounts in one Inbox. Simple as that. No switching just to see you Inbox(es)

Please note, at this time it seems this is only available on Android.