The fourth generation of the iPhone OS will soon be entering the ring.

It will run on the iPhone 3G and the third generation of the iPod Touch and of course the iPad, but only partially on the previous generation. The developers have launched a preliminary version of the iPhone OS 4.0.

More than 100 new features are expected. But the main feature that makes the most sense is undoubtedly the multitasking, hue and cry by many users of the iPhone.

Interactive advertising in Apps
you will be therefore able to move from a third party application to another by Pressing the button “home” twice, a ribbon appears at the bottom of the screen bringing the icons of open applications. You can keep them in the background, for example listen to music from an application like Spotify while responding to an e-mail.
But this will only work on the services listed by Apple: audio, voice over IP geolocalization, notifications, task execution (while the transfer of a photo on an online service for example) and switching to an application on hold.

The company explains that it is the best way to multitask without much pull on the battery or system performance. Another limitation: it will not work on the iPhone and iPod Touch second generation.
Without going into details, Apple has cited some major new features of this fourth generation OS:

The arrival of folders: the user can unite under a single icon (a folder) placed on the home screen several applications. For example, to access to all of your games with one click .

Game Community: Through the Game Center you’ll have the possibility to invit friends ,manage high scores, trophies … Innovations strangely reminding of what Microsoft offers on Xbox Live.

An enhanced messaging, combining several email accounts (Yahoo, Exchange, etc.). The ability to organize messages in threads to follow e-mail conversation and attachments associated with applications installed.
Access to the iBook library , like on the iPad. The synchronization of a book purchased will be on all platforms, iPhone, iPad …

Full of news for business: managing a fleet of aircraft, delivery of applications directly from the wireless, support for Exchange Server 2010 , VPN improved …

The other big new feature is the arrival of an advertising platform integrated in the applications. iad may well become the itching powder of the users of the iPhone.