Apple vice president of software engineering Craig Federighi demonstrates the new Yosemite operating system at the World Wide developers conference in San Francisco, California June 2, 2014. [Photo/Agencies]

Cook claimed that iOS 7 has an overall satisfaction rating of 97 percent and that "nearly half of our customers in China have switched from Android to iPhone".

According to Apple, iOS 8 builds on the clean and slick design of iOS 7. The biggest new features include new interactive notifications, health tracking, as well as many Continuity features found on the Mac.

Apple also upgraded its messages application to include features that are found on popular apps such as Tencent's WeChat and Line Corp's Line.

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Apple's long rumored foray into health and fitness came in the form of HealthKit in iOS 8. This app can keep track of various health and fitness statistics as well as seamlessly integrate third-party hardware that tracks fitness.

Another major feature of iOS 8 is Family Sharing, which allows movement of content between devices and keeps tracks of accounts. The app also has a feature that alerts parents when their children try to buy an app and allows them to complete or cancel the purchase.

The latter half of the WWDC keynote was focused purely on developers and technologies that enable tech companies.

Apple is also planning to release a big update to its software development kit (SDK). This new SDK will include application programing interface tools that help developers create applications that use Apple's hardware to the fullest extent.

On top of opening up Apple hardware to developers, the company has now put forward a software coding language called Swift. It is said to make content creation much easier, especially due to the addition of real-time monitoring.

OS X Yosemite and iOS 8 will be free when released to the general public this fall. So far there is no word on any new Apple hardware.