Apple has launched WatchKit, the development platform for its smartwatch, which will be available to consumers sometime early 2015. The Apple Watch supports apps that include both a WatchKit extension on the iPhone connected to the device, and UI elements stored on the Watch itself. This also means that, the iPhone runs the applications, and the Apple Watch sends notifications and receive instructions through voice and app actions from the user. This is pretty much similar to the Android Wear implementation on Moto 360 (or any other android Wear devices).
Apple has provided design and human interface guidelines for those building software for its wearable, too. These include suggestions and templates for different types of interfaces, tips on how to build the best home screen icons for the Apple Watch’s new unique bubble-based menu, size and layout style suggestions, as well as fonts and tips on text sizes. Apple’s smartwatch is an entirely new category, so the design language to be used on the apps built for it will differ considerably from what people are used to on their phones and tablets.
Developers will need to install Xcode 6.2 beta, and iOS 8.2 SDK that includes WatchKit to start working with the Applications and Extensions. You can have a look at the Programming Guide here.
WatchKit apps have two parts: A WatchKit extension that runs on iPhone and a set of user interface resources that are installed on Apple Watch. When your app is launched on Apple Watch, the WatchKit extension on iPhone runs in the background to update the user interface and respond to user interactions. WatchKit provides three opportunities to extend your iPhone app to Apple Watch: WatchKit apps, Glances, and actionable notifications.
It isn’t very clear on what features would Apple Watch provide; but, looking through the announcements they made sometime ago, it certainly looks like the Watch is going to have some offline functionalities, and support Apple Pay for mobile payments. Let’s hope that the Apps are not going to be resource intensive, thereby not affecting the battery life; which has been one big concern with any of the watch implementations so far.