Enlarge / The Lenovo Mirage Solo headset with its WorldSense cameras clearly visible on the front. (credit: Lenovo)

Daydream, Google’s foray into the crowded virtual reality space, has hitherto used headsets that are simply holsters, a way of holding an Android smartphone right in front of your face so that it works as a pair of VR goggles. This makes Daydream’s cost of entry cheap—the headset can be a completely passive device with no electronics of its own—which is important for making VR accessible.

Lenovo’s $400 Mirage Solo, out today, is the first standalone Daydream headset. You don’t slot a phone into this one—the device has all the hardware it needs to provide a standalone VR experience. The hardware inside the headset is certainly phone-like; it has a Snapdragon 835 processor with 4GB RAM, 64GB of storage, and a 4,000mAh battery. It also contains phone-like sensors, with a gyroscope, accelerometer, and magnetometer. But because it’s built for VR, it has a couple of extra sensors: a pair of world-facing cameras that Google calls “WorldSense.”

WorldSense is Google’s inside-out, six-degree-of-freedom motion-tracking solution. As with similar systems in Microsoft’s HoloLens and the various Windows Mixed Reality headsets, the system combines data from the device’s internal sensors with data from the cameras to track the headset’s position and orientation in space, without requiring the fixed-base stations that are used on the first-generation HTC Vive and Oculus Rift devices.