updated 02:52 pm EDT, Tue June 4, 2013
Carries over changes from web, Android apps
As promised late last month, Google has updated the iOS Gmail app to use a new inbox format. Email can now optionally be grouped into broad categories, such as Updates and Social. The most important messages are pushed into a Primary category, which is the default view in iOS. Enabling categories requires going to Gmail.com.
Joining the new inbox are more nuanced notification options. Users can choose to be notified for all messages, none, or only important ones. Separate Gmail accounts can have their own notification settings.
The app is a free download, and runs on any iOS device supporting iOS 5 or later.