Apple's iOS 5, which will run on iPhone, iPad, and iPod Touch devices, is ready to ship its gold master out to assemblers. Here, Scott Forstall talks about iOS5 at the Apple WWDC '11 in San Francisco. Reuters/Beck Diefenbach

Back in June, Apple promised that iOS 5, the massive and exciting free software update planned for the iPhone, iPad, and iPod Touch, will arrive sometime this fall, but has since provided no further clues to a specific release date. However, in a new research note released today by Ming-Chi Kuo, an Apple insider and analyst with Concord Securities, Apple has apparently put the final touches on iOS 5 and will deliver the golden master version to assemblers as early as next week, between Sept. 23 and 30.

This announcement is the next best thing to getting an actual release date, since a golden master, in hardware and software terms, is essentially the finished product, or the mold from which all other copies are mass-produced. Apple promised iOS 5 would come preinstalled on the next-generation iPhone and iPod Touch models, so the company's next step is to ship the iOS 5 golden master to a team of assemblers overseas, where it will be installed onto next-gen hardware and prepared for public release.

Apple's mega-update to its mobile platform promises over 200 new features. The biggest of all the changes is the iCloud, which is Apple's solution for free wireless syncing of files, apps, music, and photos across devices. iOS 5 also boasts a revamped notification center, a customizable newsstand that keeps magazine and newspaper app subscriptions organized, and iMessage, Apple's response to BlackBerry Messenger that allows users to send unlimited text, photo, and video messages to anyone else using an iOS device.

If, in fact, Apple's overseas assemblers receive the iOS 5 golden master next week, Kuo believes the upgraded iPhone and iPod Touch units will likely be finalized and ready to ship by the end of September. Shipping out the new devices could take an extra 10 to 12 days, he says, which would peg the release date around mid-October.

Despite a few incorrect reports in the past, Kuo has long been a proven insider to Apple products in-development. He correctly predicted the technical aspects of the iPad 2, the new line of Macbook Airs, and even production and timeline release of the white iPhone 4. Kuo also believes Apple will release its next iPhone around the same time in mid-October, which aligns well with Apple's history of product launches: Last June, the company released the iPhone 4 only three days after iOS 4. With both iOS 5 and the iPhone 5 slated for fall, there is every reason to believe that Apple history will repeat itself in 2011.

Apple CEO Tim Cook said in July that the company sold over 33 million iOS devices in its third fiscal quarter, which equates to about 363,000 iOS devices per day.