IOS 8

iOS 8 is the eighth major release of the iOS mobile operating system, designed and distributed by Apple Inc. as the successor to iOS 7 and the predecceesor to iOS 9 at WWDC 2014 alongside tvOS 8, watchOS 1 and OS X Yosemite. It features new compatibilty with OS X 10.10 "Yosemite" such as enabling Macintosh computers to intercept calls from your iPhone and be used to talk to the caller.

New features

 * Siri can be invoked with "Hey Siri" from an Apple device plugged in to power.
 * HomeKit for automating smart-home devices.
 * HealthKit for health tracking.
 * Updated iCloud with support for iCloud Drive and iCloud Photo Library.
 * Family Sharing.

Supported devices
iOS 8 was released on Wednesday September 17, 2014. It is compatible with:
 * iPhone 4S, iPhone 5, iPhone 5C, iPhone 5S, IPhone 6, iPhone 6 Plus
 * iPod Touch (5th generation)
 * iPad 2, IPad_(3rd_Generation), IPad_(4th_generation)
 * iPad Mini, IPad_Mini_with_Retina_Display IPad Air IPad Air 2

Use iOS 8 on iPhone 6 From OS X Yosemite.

Trivia

 * This is the first iOS to feature Apple Watch and Health.
 * This is the last iOS to use the original flat Music icon and the first iOS to use the new flat Music icon.
 * This is the last iOS to use the original flat Newsstand icon app.
 * This is the only iOS to update PassBook and the last to be used on iOS 8.