The generation of a spatial image takes place in the brain. Our two eyes see everything from slightly different angles. From the differences of these two images, the brain calculates the distances in the depth and thus produces the perception of the third dimension in mind.
To create something similar on a display, both eyes must obtain a slightly different image. This happens, for example, by presenting two different images adjacent to each other (side-by-side). To get together these two pictures in the brain, we then need a device that presents the left image to the left eye and the right image to the right eye. And that's exactly what the Stooksy VR-Spektiv is doing!
Several years ago, first experiments with 3D or VR (Virtual Reality) goggles and displays were performed. However, the first of these devices offered only low resolutions, were very clunky and so heavy that one could hardly bear them on the head. They also needed a wired connection to a larger computer, whereby its application was greatly limited.
Currently, the best-known and technically leading representative under the VR headsets is the Oculus Rift. This system uses a fixed built-in display, which still gets its content from a computer. Meanwhile, the connection to the computer also works wireless, but the system cannot be used independently (afaik). Even if this VR headset still represents the leading edge of technology at the moment, it is very expensive for private use and newly developed applications are not readily available for the mass market. Therefore, we expect that this system will occupy only a relatively small niche in the future. (Maybe things have changed since Facebook took over Oculus ... :-))