iOS 9:
Main areas of focus: Stability, Developer API additions, new core technologies
Device support added in this release: iPhone 6S, iPad Air (3rd generation), iPad mini (4th generation)
Device support dropped in this release: iPhone 4S, iPad (2nd generation), iPod touch (5th generation)
Other notable changes: The iPod touch will cease to exist as a product Apple sells with the release of iOS 9.
Release date: Wednesday, October 21, 2015 (for existing devices) / Friday, October 23, 2015 (for newly added devices the same date those devices themselves become available)
iOS 10:
Main areas of focus: Accessibility, "Grand Unification" of APIs
Device support added in this release: iPhone 7, iPad Air (4rd generation), iPad mini (5th generation), iPad Pro (1st generation)
Device support dropped in this release: iPhone 5, iPhone 5C, iPad (3rd and 4th generations)
Other notable changes: The iPad Pro will likely have a custom build of iOS 10, which will more closely resemble OS X on a laptop. Swift 1.3 will be released.
Release date: Wednesday, October 19, 2016 (for existing devices) / Friday, October 21, 2016 (for newly added devices the same date those devices themselves become available)
OS X 10.11:
New features: UXKit framework - "The bridge between iOS and OS X developers have been waiting for"; Siri makes its debut on OS X
API changes: Carbon switches to "Run-only" mode. The headers for compiling Carbon apps will go away as a result.
Developer tools changes: Swift 1.4 will be released alongside Xcode 7.
Supported Mac changes: Support dropped for all 2007 Macs and some 2008 Mac models.
Other interesting notes: Apple will pick a marketing name for 10.11 from the remaining pool of California place names. Which one they'll use is anyone's guess, but I think "Corona" is a likely choice.
OS X 10.12:
New features: "Grand Unification" of APIs, stronger core (like Snow Leopard)
API changes: Apple Java 6 support is removed.
Developer tools changes: Swift updated to 1.5. Xcode updated to 7.x as well (exact number depends on the number of iterations of iOS 9).
Supported Mac changes: Support dropped for remaining 2008 Macs.
Other interesting notes: Apple will once again pick a marketing name for 10.11 from the remaining pool of California place names. Which one they'll use is anyone's guess, but I think "Modesto" is a likely choice.
Beyond iOS 10 and OS X 10.12:
This is where things get REALLY interesting. There are several paths Apple could take at this juncture: Bumping OS X to OS XI upon the release of iOS 11 is one of them. Also a strong possibility is the first ARM Macs being unveiled.
Main areas of focus: Stability, Developer API additions, new core technologies
Device support added in this release: iPhone 6S, iPad Air (3rd generation), iPad mini (4th generation)
Device support dropped in this release: iPhone 4S, iPad (2nd generation), iPod touch (5th generation)
Other notable changes: The iPod touch will cease to exist as a product Apple sells with the release of iOS 9.
Release date: Wednesday, October 21, 2015 (for existing devices) / Friday, October 23, 2015 (for newly added devices the same date those devices themselves become available)
iOS 10:
Main areas of focus: Accessibility, "Grand Unification" of APIs
Device support added in this release: iPhone 7, iPad Air (4rd generation), iPad mini (5th generation), iPad Pro (1st generation)
Device support dropped in this release: iPhone 5, iPhone 5C, iPad (3rd and 4th generations)
Other notable changes: The iPad Pro will likely have a custom build of iOS 10, which will more closely resemble OS X on a laptop. Swift 1.3 will be released.
Release date: Wednesday, October 19, 2016 (for existing devices) / Friday, October 21, 2016 (for newly added devices the same date those devices themselves become available)
OS X 10.11:
New features: UXKit framework - "The bridge between iOS and OS X developers have been waiting for"; Siri makes its debut on OS X
API changes: Carbon switches to "Run-only" mode. The headers for compiling Carbon apps will go away as a result.
Developer tools changes: Swift 1.4 will be released alongside Xcode 7.
Supported Mac changes: Support dropped for all 2007 Macs and some 2008 Mac models.
Other interesting notes: Apple will pick a marketing name for 10.11 from the remaining pool of California place names. Which one they'll use is anyone's guess, but I think "Corona" is a likely choice.
OS X 10.12:
New features: "Grand Unification" of APIs, stronger core (like Snow Leopard)
API changes: Apple Java 6 support is removed.
Developer tools changes: Swift updated to 1.5. Xcode updated to 7.x as well (exact number depends on the number of iterations of iOS 9).
Supported Mac changes: Support dropped for remaining 2008 Macs.
Other interesting notes: Apple will once again pick a marketing name for 10.11 from the remaining pool of California place names. Which one they'll use is anyone's guess, but I think "Modesto" is a likely choice.
Beyond iOS 10 and OS X 10.12:
This is where things get REALLY interesting. There are several paths Apple could take at this juncture: Bumping OS X to OS XI upon the release of iOS 11 is one of them. Also a strong possibility is the first ARM Macs being unveiled.
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