Apple is gradually filling in the blanks about how its forthcoming Apple Watch will function ahead of the device's possible release this quarter.
Apple's iOS 8.2 SDK beta with WatchKit has been available since November, giving developers the tools they need to create apps, notifications and Glances for Watch.
WatchKit documentation already revealed that Watch apps won't run totally natively but be split in two. While a WatchKit app resides on the Watch, a WatchKit "extension" on a paired iPhone handles a number of tasks that help present different interfaces on the Watch itself such as the new Glance option. Offloading the processing of say health data collected from the Watch to an iPhone also offers a way of conserving limited battery resources on the Watch, which is estimated to be about one whole day.
Apple has also released several iterations of the iOS 8.2 beta, with the fourth version rolled out yesterday. iOS 8.2 beta 4 introduced a new item in the Bluetooth Settings menu dedicated to pairing an iPhone with the Apple Watch, according to 9to5 Mac.
The ability to pair devices over Bluetooth holds the key to much of the a Watch app's functionality, given an app's tandem operations on both the Watch and an iPhone.
Another key piece of information that came in yesterday's update is that there will be a dedicated Apple Watch app to be installed on the iPhone. Although Apple has mentioned this previously, as 9to5 Mac notes, the latest beta confirms it will require an app. This app becomes the primary interface for setting up and controlling an Apple Watch, suggesting an early preview-based review last September was correct.
The Watch app isn't actually available yet but the fact that the latest iOS 8.2 beta includes these two items suggests Apple is approaching the point of being ready to release the Watch, which is rumoured to happen in March.
Previous iOS 8.2 updates have introduced or rather reintroduced new features for Apple Health, including blood glucose tracking. Of course, like other wearables, Apple Watch will feature a number of health tracking tools, including an accelarometer, heart-rate sensor, wifi and GPS, but will also introduce new interface elements via its "Taptic engine" which produces different sensations on the wearer's skin for different interactions.
Watch owners will also be able to 'ping' their iPhone - get it to make a sound to help an owner track it down if it's been misplaced - as one keen-eyed observer spotted in Apple's promotional site for the Watch.
The Apple Watch will cost from $349, though what consumers actually pay in the end will largely depend on the cost of the range of wristbands Apple will make available.
Apple has so far not given an official release date for the Watch, saying only it will be made available in "early 2015". However, rumours have it that the device will be released in March.
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