Apple's CEO Tim Cook attends the Apple Worldwide Developers Conference (WWDC) 2015 in San Francisco, the United States, June 8, 2015. [Photo/IC]

Operating system, or OS, is software that manages hardware and software resources and provides a platform for more specialized functional applications, or apps.

Some other changes unveiled on Monday include new features for Apple Pay and in Maps navigational app, a new app known as News, and a new service dubbed Apple Music.

Chinese Apple fans are eagerly following the tech giant’ 26th annual Worldwide Developers Conference although it is taking place at midnight, Beijing time.