While the world awaits a true consumer version of a virtual-reality headset like the Oculus Rift or Sony's Project Morpheus, the smartphone is emerging as an amuse-bouche for the VR appetite: Demo versions of the Samsung Gear VR already are appearing in Best Buy stores. But at a rumored $200, and another four times that for the Galaxy Note 4 phablet you need to use with it, the Gear VR is a steep investment for people looking for a holdover.

To address that gap in the market, several manufacturers are developing cheaper versions of the Gear VR's "viewfinder" model—stripped of all hardware and relying on your smartphone's display and accelerometer/gyroscope array to provide a virtual experience. Most, like the Dodocase Smartphone VR Viewer, ape Google's Cardboard kit, which the company distributed at their I/O conference earlier this year. They're cheap and they're clever, but they're leaving a fairly wide gap in the market. Now, one company has decided to jump into the gap, and it's a surprising one.

Carl Zeiss is primarily known for optics; while in truth that only accounts for a small fraction of a multibillion-dollar corporation, it's the company's camera lenses we're most familiar with. Now a small team within the company is leveraging that reputation into a $99 headset called the VR One. And in a move straight out of Oculus' playbook, Zeiss is entrusting its growth to the developer community.

Everything about it is open, in fact, from the SDK to the smartphone you use it with—as long as it's iOS or Android and has a display between 4.7 inches and 5.2 inches. (Sorry, Cortana.) Phone-specific trays ensure the phone is properly aligned with VR One's internal lenses and an aperture for the phone's camera, which enables augmented-reality experiences in addition to virtual ones. The first available trays will fit the iPhone 6 and Galaxy S5, with future trays determined by customer and developer feedback.

The good news is the VR One arrives in December. The bad news is Zeiss has almost no idea what to do with it. The internal team at Zeiss developed two demo apps—a photo viewer and an AR proof of concept—to show what it can do, but based upon our hands-on with an early version, it lacks any compelling gaming or media experiences, or even a mechanic that lets you select and launch VR apps from inside the viewer. To help address those shortcomings and spur interest, Zeiss is planning a contest for developers, which they'll publicize on a dedicated Tumblr page for the VR One. And if all goes well, before 2015 rolls around you'll have a well-built mobile VR solution that won't break the bank.