Apple Watch Basics

Every Apple Watch must be paired with an iPhone 5 or newer in order for you to install apps. While a cynic might see this as a sneaky way for Apple to double up on device sales, you’ll see in our in-depth chapter on WatchKit extensions,, that there’s a very good reason: all of the processing in your app is performed on your user’s iPhone and transmitted to Apple Watch. This is one example of a constraint placed on the device to improve battery life. Instead of your app trying to use the watch’s processor to do something intensive, like mine bitcoin, it’ll ask the phone to perform difficult tasks, freeing up its processor for UI updates (although, seriously, don’t try to mine bitcoin on your iPhone). So for your watch app to ...

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