Google's Material Design UI elements are likely most commonly thought of as a design style seen throughout a wide selection of different Android apps, but Material Design isn't just for the Android system or Android apps. Material Design actually spans across multiple platforms, including desktop, and today during the Google I/O developer conference Google has just posted up the Material Design Guidelines for Wearables. Although material design elements can already be seen throughout much of the Android Wear platform, having the guidelines laid out there for all means developers will have a clear and concise set of design paths to follow when creating their apps for Android Wear.
The underlying principles of Android Wear are about offering users the right information at the right time, which makes it less surprising that Google starts off the guidelines by mentioning a few key traits for material design on the platform, the first of which is timeliness. Android Wear design should be timely, so users can stay connected to the watch on their wrist as well as to the people and places that are around them in the physical world. The UI design of any Android Wear app should also be glanceable, making it possible for a user to quickly look down at their watch and get the information that they need without having to spend too much time at this stage of interaction. Things need to be easy to tap as well which means large buttons that are simple to hit and easy to see, and drawing things back to the presence of time, interactions with Android Wear should be saving users time as opposed to taking longer than simply interacting with the phone the watch may be connected to. You can see Google's examples from the gallery of images below which touch base on these specifics.
Moving beyond the design basics, Google states that developers should be focusing on the functionality of their core apps when designing an app for Android Wear and that their Android Wear app should be supporting their core app. The main thing that Google seems to be inferring is that most elements of the app design should be as simple as possible. That's the keyword - simplicity. Task completion within apps should be simple and unencumbered as should the functionality of the app, and naturally, Google recommends that developers test their designs on an actual watch to see how things look and feel, because there is no better idea of how things will be than getting a feel for the app in the real world, on a real watch. Also part of the guidelines, Google gives some examples of app design to help developers along with what their app should look like. The guidelines have quite a bit more information, so if you're a developer looking to design your first Android Wear app or if you'll be working on a revision of an existing one, the Material Design Guidelines for Wearables should assist in following the correct path and making things as smooth as possible.