I access my (multiple) Gmail accounts almost entirely through the Mailbox app (on my iOS devices) and through Sparrow (on my Mac).
As such, I didn't get the "welcome to the tabbed inbox" message in Gmail until today, when I happened to login via the web client to do a more complex search.
So, here's my question:
Do the tabbed inboxes do anything that's visible/accessible in an email client (adding labels, etc.), or are they basically just a custom view in the webapp that's based on attributes that are hidden from the end user?