Apple has made a habit of introducing game-changing software at its annual Worldwide Developers Conference, and this year appears to be no different, as the company unveiled the next installments of its mobile and Mac operating systems, as well as a new cloud computing service.

As expected, Apple CEO Steve Jobs took the stage to introduce the new iCloud, a cloud-based service designed to enable users to sync apps, media, mail, calendars, documents and other data between multiple devices, including smartphones, tablets, laptops and desktop computers.

All content stored in iCloud is automatically and wirelessly updated among devices, and updates are pushed out almost instantly, according to Apple.

Apple also unveiled the next version of its mobile operating system, iOS 5. In addition to iCloud syncing, the new mobile OS introduces more than 200 features, including Notification Center, iMessage and Newsstand.

Both iCloud and iOS 5 will be available this fall.

iCloud is undoubtedly Apple's response to similar cloud-based services offered by Google, including Gmail, Google Docs and Picasa. As more cloud services are introduced, research firm Forrester predicts the cloud market to reach more than $240 billion by 2020.