Apple Inc. (NASDAQ:AAPL) is expected to introduce two new iPhone models on Tuesday, but the company also plans to release new software to accompany its new mobile hardware. Unfortunately for those who can’t wait for iOS 7’s initial release date in mid-September, it doesn’t look like iOS 7 will be supported by all iOS devices at first.

Last month, 9to5Mac’s Mark Gurman said the iPad version of iOS 7 was “running behind,” and rumors since then have indicated Apple won’t have the iPad version of iOS 7 ready by Sept. 10, which is when the company is expected to release the gold master version of iOS 7 to developers. Apple has released six separate betas of iOS 7 thus far. In all likelihood, iOS 7 won’t be ready to release on the iPad until October.

But why the delay of iOS 7 for iPad? Well, first, the iPad and iPad mini didn’t support iOS 7 until the release of iOS 7 beta 2, which gave iPhone developers a two-week head start on optimizing their applications for Apple’s newest mobile operating system. But the likely reason to the delay iOS 7 for iPad is simply strategy: In the same way new hardware deserves new software, Apple probably wants to make the release of its new iPads in October more profound. If iPad users get a full month and a half to play with iOS 7 on their current iPads before the new ones come out, the new iPads might seem less attractive or less “new.”

The bottom line: Bunding the release dates for new hardware and software has successful for both the iPhone and iOS, and Apple simply wants to apply the same formula to the iPad.

The release of iOS 7 for iPad will likely accompany Apple’s new Mac software, OS X Mavericks, which is also expected to launch in late October. With the company’s product release date formula in mind, the introduction of OS X Mavericks may coincide with some new Mac hardware, including new iMacs and MacBook Pros powered by fourth-generation Intel Core Processors, code-named Haswell. Apple could introduce these computers on Sept. 10, but we don't believe the company will have enough time talk Mac since a majority of the time will presumably spent addressing iOS 7, iWork and iLife, and its two new iPhones.

Of course, if you don't want to wait until October to have iOS 7 on your iPad, you can download an iOS 7 beta to your iPad or iPad mini right now.

About iOS 7

Introduced at the Apple Worldwide Developers Conference, or WWDC 2013, in June, iOS 7 is the first redesign of the company’s mobile operating system since the introduction of the original iPhone in 2007.

Apple has completely revamped the classic icons, colors, style and textures of iOS to make it feel simpler yet more sophisticated. The interface acts like a series of layers, which provides context in a way that makes navigation feel even more intuitive than before.

But iOS 7 isn’t just a cosmetic release: Apple added dozens of important features and tools to make the new iOS more productive. Most notable among the new iOS 7 features are the helpful Control Center that provides quick access to important settings; the built-in parallax that shifts the background image in response to one’s movements; a new way to multitask apps; the AirDrop feature for sharing photos or documents with other iPhone users in the area; and many others.

For more on iOS 7, check out our visual guide on iOS 7 to learn more about the new design, some surprise features we discovered in the very first iOS 7 beta and our collection of 80-plus screenshots of iOS 7.

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