The dates for this year's Worldwide Developers Conference (WWDC) have already been announced, so now it's the time when rumors are focusing on what Apple will release and discuss during the five-day-long event.

Rumors about Apple's next mobile operating system, iOS 7, are making the rounds and the OS is being dissected.

According to a report by 9to5 Mac, the iOS 7 is going to be very new in terms of looks and commands. The report says that people who are very familiar with the operating system will find it a bit difficult to get accustomed to it initially. The report suggests that the new user interface (UI) of iOS 7 is codenamed "Innsbruck."

"The interface changes include an all-new icon set for Apple's native apps in addition to newly designed tool bars, tab bars, and other fundamental interface features across the system," the report states. The website claims to be getting all these details from different sources close to the iOS 7 development team.

The UI is going to be very flat, unlike the present iOS 6. This point may also disappoint loyal users of iOS, as the skeuomorphic gloss presently on the icons will be washed off in the new UI.

New polarizing filters would be something many users will look forward to, as this new feature is going to provide them more security while using their iOS 7-based devices in public or crowded areas. The filters are expected to decrease the viewing angle of the screen so people cannot peep into your device when you are busy typing your text messages.

The new mobile operating system from Apple is expected to make its debut during the upcoming WWDC and this report strengthens the rumors of the new iOS reaching the WWDC main stage.

A leaked document from a Japanese carrier also shows that the iPhone 5S will be available for preorder June 20. That is just six days after the concluding day of the WWDC.

We can expect the release of the iPhone 5S during the WWDC and iOS 7 might also be found inside the A7-powered smartphone from Apple.