Apple CEO Tim Cook takes the stage during Apple's Worldwide Developer Conference (WWDC) at the San Jose Convention Center in San Jose, California, the United States, June 4, 2018. (Xinhua)

SAN FRANCISCO, June 4 (Xinhua) -- The Apple Worldwide Developers Conference (WWDC) 2018 started Monday in Silicon Valley, the United States, with the launch of new updates and productivity tools for iOS, macOS, watchOS and tvOS.

Apple CEO Tim Cook, who hosted the event, welcomed thousands of developers from over 70 countries and regions to WWDC 2018.

Apple released new updates for macOS with dark mode, which redesigned App Store, App News and a bunch of other new features.

Cook said the update Mojave's new features will be made available to the public this fall but a beta version will possibly start this summer.

Mojave's dark mode turns the dock, taskbar, and the chrome around all apps into a dark gray.

Craig Federighi, Apple's senior vice president of Software Engineering, introduced at the event iOS 12, said Apple in a statement.

Apple software senior vice president Kimberly Beverett demonstrated new features in Siri Shortcuts, such as ordering a coffee in the morning or making travel plans.

LEGO's director of innovation Martin Sanders also demonstrated LEGO AR City, which uses ARKit 2 features including shared experiences, persistent Augmented Reality and 3D object detection.

Cook said at the conference that the number of Apple's global developers has surpassed 20 million in over 70 countries, yielding a gross revenue of 100 billion U.S. dollars.

He said App Store has become the world's largest apps market visited by 500 million users every week.

The Apple WWDC, which was first inaugurated in 1983, will last five days till Friday.