In 2016, Apple’s board of directors gathered inside one of its buildings in Cupertino, Calif., for a glimpse into the company’s future.

Former Vice President Al Gore, then–Disney CEO Bob Iger and other Apple board members walked from room to room, trying out prototype augmented and virtual reality devices and software. One of the gadgets made a tiny digital rhinoceros appear on a table in the room. The creature then grew into a life-size version of itself, according to two people familiar with the meeting. In the same demo, the drab surroundings of the room transformed into a lush forest, showing how users could seamlessly transition from AR, in which they can still view the physical world around them, to the more immersive experience of VR—a combination known as mixed reality.

The prototypes weren’t exactly the lustrous products the company is known for. Many were cobbled together from off-the-shelf parts and ran on Microsoft’s Windows operating system, software Apple normally keeps its distance from. Several were jury-rigged HTC Vives, one of the few commercially available VR headsets at the time. At least one was so heavy that it had to be suspended by a small crane so the Apple board members could wear it without straining their necks, the two people said.