In mid-2013, Google updated the Gmail inbox with tabs which allow the application to categorize the user’s emails.
The five tabs are: Primary, Social, Promotions, Updates, and Forums.
These tabs also appear in Gmail’s mobile version. In addition to customization options, the entire update can be disabled, allowing users to return to the traditional inbox structure.
The Gmail Labs feature, introduced on June 5, 2008, [28] allows users to test new or experimental features of Gmail, such as bookmarking of important email messages or custom keyboard shortcuts. Users can enable or disable Labs features selectively and provide feedback about each of them. This allows Gmail engineers to obtain user input about new features to improve them and also to assess their popularity. Popular features, like the "Undo Send" option, often "graduate" from Gmail Labs to become a formal setting in Gmail.[29] All Labs features are experimental and are subject to termination at any time.