Apple holds their World Wide Developers Conference (WWDC) 2015 at Moscone Westin in San Francisco, the United States on June 8, 2015. It is being reported that Apple will debut a new streaming music service and updated iTunes Radio, and new versions of OS X 10.11 and iOS 9. [Photo/IC]

Apple Inc unveiled new operating systems for smartphones and computers and a new music streaming service on Monday at an annual event in San Francisco.

With Chief Executive Officer Tim Cook delivering a keynote address, the company kicked off the Worldwide Developer Conference (WWDC) of the year with a series of announcements for software upgrades or improvements.

About the new OS X, for Macintosh computers, Cook said it brings "a whole bunch of new capabilities" to the machine. And the iOS 9, for iPhones and iPads, comes with a new "proactive assistant" system designed to learn users' musical taste and help users coordinate events. In addition, Apple introduced Watch OS2, for Apple Watch.