On Sept. 18, Apple users will be able to download Apple's latest software, iOS 7. The new software will be available for download via iTunes on the iPhone 4, iPhone 4S, iPhone5, and the upcoming iPhone 5S and iPhone 5C. Users will also be able to download iOS 7 on their iPad 2, iPad with Retina and iPad Mini. The announcement was made yesterday at Apple's launch event in Cupertino, Calif.

"The iOS 7 is the biggest change to iOS 7 since the introduction of iPhone," Tim Cook, Apple CEO, said during Apple's Worldwide Developers Conference in June.

The biggest new features of the iOS 7 include the AirDrop and Control Center.

With AirDrop, Apple becomes more on par with some of its competitors. AirDrop allows users to share items like videos, contacts and photos from any app with a Share button. AirDrop then sends the item via Wi-Fi or Bluetooth through a secure network.

The Control Center will give users easy access to commonly used apps and commands such as Airplane mode, brightness display , Wi-Fi control, Bluetooth, Do Not Disturb, Lock screen orientation and music control. All that is needed is a quick swipe to access tools like iOS 7's new flashlight, as well customer favorites like the calculator, camera and timer.

The Notification Center will also be upgraded. Typically, the Notification Centers shows users their new mail, to-do list, missed calls and similar news. iOS 7 adds a feature called "Today." With Today, the iPhone will display all of the news of the day including weather, traffic, and birthdays. As usual, the Notification Center will be accessible from any screen by swiping down. With iOS 7, the Notification Center will also be accessible through the Lock screen.

No major upgrade is complete without a makeover. The new iOS will have a "flatter" design. Apps like Notes and Weather are re-designed. Changes in iOS 7 include adjustments to the size and shape of app icons and other commonly used items, as well as differences in iconography and typography. The app icons for iOS 7 will now feature a "superellipse" shape.

Apple has also made iOS 7 refresh popular apps according to the user's tendencies. For example, if a user usually checks his or her Facebook app at 12 p.m. daily, then iOS 7 will refresh the app for the user at that time when his or her phone is in a low-power mode (such as when it is on and connected to Wi-Fi.)

In addition, Apple's app store will show shoppers "Apps Near Me," which are apps popular in the user's area. Downloaded apps will also update themselves automatically.

In addition to a release date for iOS 7, Apple also announced that iOS 7 features a radio. The live streaming music service called Apple Radio will serve as a competitor to other web-based radios such as Pandora and Spotify. Apple Radio will allow users to customize stations based on their musical preferences. Users will also have the option of buying songs through Apple Radio.

During yesterday's event, Apple revealed that Apple iOS apps will be available for free immediately.

"Starting today, all of Apple's iOS apps-Pages, Numbers, iPhoto, iMovie, etc-will be free on a new iPhone/iPad/Touch," David Pogue, New York Times tech columnist, said via Twitter.

In addition, Apple confirmed that Siri will be re-vamped in iOS 7 to include Wikipedia and Twitter in its searches.

iOS 7 will have improved, more distinct ringtones available as well.