Augmented reality (AR) is poised to become the next medium for computers, but the hardware, software, and overall user experiences still have ways to go before they reach the portability and sleekness science fiction have conditioned us to expect and want as part of our everyday lives. Fortunately, the advancement of mobile AR experiences (Snapchat, ARKit, and ARCore), coupled with work developers and designers have done on head-mounted displays (HMDs) like the Meta 2, have brought us all one step closer to that reality.
That future we've been wanting is almost here thanks to developers like Preston McCauley (shot through the Meta 2).
Now, for those who have been creating apps for both mobile AR and highly immersive AR, we salute you for understanding and developing across different form factors. Smartphones and HMDs present different design challenges and considerations (in fact, we explored some of these challenges through our spatial interface design principles and AR user interface guidelines a while ago). And while there are a wide variety of different guidelines out there, we strongly recommend diving into all of them, and then comparing and testing them against one another to see which guidelines work best for the kinds of apps and experiences you're creating.
As you get started on your development journey, we wanted to recommend some of our principles and guidelines, along with this introductory book on designing for mixed reality written by our very own Kharis O'Connell. To begin, you can think of the spatial design principles and UI guidelines as two sides of the same coin: the principles are the theory (backed by over two years of user experience and neuroscience research) and the guidelines are the implementation and actual practice of the principles, i.e., where the proverbial rubber meets the road.
Spatial Design Principles
For the past 50 years, we've interacted with computers and the digital world through 2D screens (our smartphones, laptops, and desktop computers), while our world has remained very much 3D. AR as a computing platform integrates the digital world into our real-world environment. "Think spatial" is a simple reminder to think beyond the screen, and fully embrace and utilize the space and environment around each and every user. Content and apps can now reside and be organized as if they were in an extension of a user's workspace or desk.
Avoid Surprises and Magic Tricks
Unless you're intentionally creating experiences filled with horror or fantasy elements, AR apps should shy away from quirks and surprises that don't match up with what users are expecting. For example, users waving a holographic wand expect "magic" to happen, but not so much the wand to erase things that they're seeing in front of them:
User Interface Guidelines
Given that holographic objects need to mirror their real-world counterparts as closely as possible, it's important to keep in mind depth cues such as occlusion, lighting, and shadows. What's especially key is to consider the feedback mechanism for interacting with holographic objects. The current generation of AR HMDs lack tactile feedback (haptic feedback hardware is still rather large and unwieldy, and thus difficult to integrate directly into HMDs), so visual cues such as animations and lighting will help users understand when they've successfully grabbed a holographic object or moved it around.
In the Meta 2, two blue rings track and indicate where your hands are, and "close up" when
your hands make a fist / grab holographic objects (Preston McCauley; shot through the Meta 2).
One aspect of the user experience that you especially need to consider is the user's comfort while wearing a headset (or even when you're wearing the headset while developing in it). And while each headset has different ergonomics, it's best to tailor your apps to each headset's recommended head movement and rotation specs so that users can focus on your app experience, instead of their fatigue.
Based on our research, we've found that rotating your head in a 30° arc (while seated) is the most comfortable way to see and interact with holographic objects while wearing the Meta 2.