With iOS 9 SDK during WWDC 2015, Apple introduced some very big changes, including the introduction of watchOS 2 which really changed how we interact, as programmers, with the ?Watch. Previously, almost all requests had to go to the companion iOS device from the watch and then served by the iOS app. With watchOS 2, the watch takes a lot more responsibilities and can update its content almost always by itself.

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http://www.rarefile.net/51pmnapfdtj9/iOS9SwiftProgrammingCookbook.rar
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