iPhone and iPod Touch owners will get even more from their devices with the release of more than 100 new features in the free OS4 upgrade. Due for release in the Australian winter, the most notable improvements offered by OS4 include multi-tasking, a hub for social gaming called Game Centre, and a controversial feature dubbed iAd that allows developers to embed advertisements directly into their apps

The multi-tasking feature sees Apple devices catch up to handsets supporting rival platform Android, and will allow owners of 3GS iPhones and third generation iPod Touch devices to run and quickly switch between applications by tapping the home button twice to display a multitasking tray. This allows, say, audio from a music app to play while another app is in use, or VoIP calls to be received while the phone is running another apps or in sleep mode.

Apple says iAd will allow people to enjoy full screen mobile ads without the inconvenience of having to leave the app they’re in and click through to a web browser. While this is doubtlessly handy for advertisers, we can see a real nuisance value for users.

More significantly, by bypassing the likes of browsers such as Google and Bing, iAd theoretically signals Apple’s entry into the ad serving business, the profits from which could be immense. Consider the recipe: the company has a monopoly over the App store, which has delivered more than 40 billion-odd apps in the two-and-a-bit years since launch. To boot, there is a gobal install base of more than 50 million iPhones, according to Apple. Add it up and the result is “ka-ching”!

Games and other stuff

As another key upgrade to the current operating system, Game Centre provides a social network that allows gamers to play against friends or unknown other players in multiplayer games, with random players located via a feature called thanks to a feature called Matchmaking.

Other new features to be offered by OS4 include tap-to-focus for video, 5x digital zoom for the camera module, Bluetooth keyboard support, the ability to gift apps to the and the ability to arrange apps into folders. OS4 will also provide entrée into Apple’s new iBookstore, which launched with the company’s iPad in the US last week. The online ebook store is currently available only to residents of the US.

Apps developed for the iPad have been built using the current OS 3.2 platform. A version of OS4 will be made available for the iPad later in the year, according to Apple.