How to undo the changes caused by the June 2013 updates to GMail.
I was checking my Gmail account via the official app on my phone yesterday and all of a sudden my Inbox was called Primary and half my e-mails were missing. There were also new categories called Social, Promotions, and other listed. I’m a heavy user of filters in Gmail and if an e-mail gets to my Inbox I want to read it, darn it.
When I refreshed the browser based GMail I had the same issue. After some digging I found the solution and thought others might want it to.
To get the old Gmail Inbox back click on the gear icon in the upper right corner of the web version of Gmail, then click on the Inbox tab and change your settings to this:
Save these settings and the problem will be fixed on both desktop and mobile (iOS and Android).