iOS 4 is compatible with iPhone 4, iPhone 3GS and iPhone 3G, as well as recent generation iPod touch. Multitasking is only available with iPhone 4 and iPhone 3GS. iOS 4 also comes preinstalled on the new, $99, 8GB iPhone 3GS, as well as the next-generation iPhone 4, set for release this Thursday.
These are the new features of iOS 4 highlighted by Apple:
* Multitasking: Now you can run your favorite third-party apps —- and switch between them instantly —- without slowing down the performance of the foreground app or draining the battery unnecessarily.
* Folders: Organize apps into folders with drag-and-drop simplicity. Get faster access to your favorites and browse and manage up to 2160 apps.
* Even better Mail: See messages from all your accounts in a unified inbox, organize messages by threads, open attachments in third-party apps, and more.
* iBooks: More than a great ebook reader, iBooks is also an amazing place to browse and shop for books, day or night.
