After a little over a year of development, elementary is proud to announce the stable release of elementary OS Loki." The new version includes many new features, such as a new software manager called AppCenter. New natural language processing has been added to the calendar application and the distribution now ships with the Epiphany web browser. Desktop notifications have been revamped too for the 0.4 release: "The brand new Notification Center catches notifications from apps and lets you see and act on them later. It also provides a handy system-wide Do Not Disturb toggle. By default, all apps show in the Notification Center, but you can disable noisy apps in the Notifications section of System Settings. The Notification Center is powered by the FreeDesktop notifications specification, so any apps following this open standard will work automatically.