New rumors backed by the BETA Cycle updates seem to suggest that Apple will not release iOS 8 and OS X on the same date, or anything closer, but over a month away.
According to unnamed sources, Apple is going to release the next BETA of iOS 8 (version 5) as soon as August 4th, just two weeks after the release of BETA 4. Apple will also launch the iOS 8 BETA 6 on August 15th and get the GM ready for prime time at the beginning of September.
The original rumored release calendar was saying that Apple would launch iPhone 6 along with iOS 8 and OS X Yosemite on September 19th, and that everything was going to be available a week later, on September 25th.
iOS 8 BETA 4 was released on Monday, July 21st, and it is considered the most stable beta so far. However, Apple has got enough time to iron out the wrinkles and release the new firmware. Up until now, users have noticed just minor issues with the iOS and 3rd-party apps.
On the other hand, Apple has changed the look and feel of iOS with this release: a new Control Center UI came alongside new features and settings, as well as some new default apps.