With today’s release of the Apple Watch WatchKit SDK, we’re seeing some new information about Apple’s upcoming wearable device.
According to Apple’s human interface guidelines, the two separate Apple Watch models have different screen resolutions. The smaller 38mm Apple Watch has a resolution of 272 x 340, while the larger 42mm Apple Watch has a resolution of 312 x 390. In the WatchKit documentation, Apple refers to the Apple Watch display as “Retina,” and instructs developers to use 2x image assets.
Developers are directed to provide image assets for different screen sizes “as needed.” While developers can use the same image resources if they display well on both screen sizes, they will be required to provide separate screen resources if needed.
Icons on the Apple Watch will be of variable sizes, based on screen size and type. Notification Center icon should be 29 pixels for the 38mm Apple Watch, and 36 pixels for the 42mm Apple Watch, while a home screen icon on the smaller screen should be 172 pixels, and a home screen icon for the larger watch display should be 196 pixels.
The WatchKit guidelines also allow us to see how Apple sees the Apple Watch’s place in the scheme of things.
According to Apple, the Apple Watch aims to “blur the boundaries between physical object and software” through the Digital Crown navigation tool, the Taptic Engine for subtle alerts, and Force Touch, a new touch control system. Thoughtful design, says Apple, “should contribute to this experience of hardware and software feeling indistinguishable.”
Apple also suggest that developers keep content created for the Apple Watch “lightweight,” keeping interactions simple and “accessible and dismissible quickly and easily, for both privacy and usability.” The context of apps are intended to be accessed, “briefly, frequently, and on a small display.”
Apple released the WatchKit development software as part of an Xcode 6.2 beta earlier today, alongside a beta of iOS 8.2. Developers can immediately begin developing actionable notifications, Glances, and iPhone-driven apps for Apple’s upcoming wearable, and they will be able to create “fully native” apps “later next year.”
