The company's iOS 8 beta 4, which arrived last week, includes features not present on previous versions, including a new Tips app. The beta also includes enhanced dictation, live feedback, and more. Because of these many changes, I expect that Apple will release at least one more beta before offering developers a GM version.
Last week, BGR said that Apple plans on releasing iOS 8 beta 5 next Monday, Aug. 5, followed by the launch of iOS 8 beta 6 on August 15. The GM, or final version, would arrive a few weeks later.
This sounds about right, although our own Apple contacts say the release schedule remains highly fluid.
First unveiled in June, iOS 8 should be released to the public in September. It features new Photos and Health apps, improved iMessages, and much more.
See also: Apple’s ‘iPhone 6’ event may be in mid-September this year, Apple to launch iOS 8 and OS X Yosemite separately despite tight integration features, and Numerous app developer previews their Notification Center widget for iOS 8.