Has Samsung found the holy grail for mobile virtual reality? That’s a question VR enthusiasts have been pondering ever since the consumer electronics giant released a teaser video for Unpacked, its press event at the Mobile World Congress in Barcelona this weekend.

Samsung is expected to unveil the Galaxy S7 handset at Unpacked, but the video didn’t actually show the new phone. Instead, it featured a young man putting on a Gear VR headset, looking around, then leaning forward, and reaching for — something.

This has led to numerous speculations in the VR community, because until now, what’s shown in the video just hasn’t been possible with Samsung’s Gear VR.

That’s because the Gear VR doesn’t have a feature that’s known in the industry as positional tracking. In a nutshell, positional tracking is a way for a VR headset, and apps running on it, to know what a user is physically doing.

Why positional tracking is so important

Facebook-owned Oculus has made positional tracking a key component of its Rift VR headset. The $600 headset will come with an external sensor that looks a bit like a designer desk lamp when it ships next month. Pointed towards the user, this sensor can keep track of head (and by proxy body) movements within a small predetermined space.

Users can’t quite walk around freely; after all, the Rift headset still requires cables to plug into a PC. But it’s enough to duck and move out of a way when a virtual dinosaur approaches, move towards or away from objects, head a virtual soccer ball or even just feel that you’re really there within any VR experience.

HTC’s Vive headset takes the same concept even further, and uses two so-called lighthouse trackers to keep tabs on a user within a 10×10-foot space. This has allowed for amazingly immersive experiences, which include the ability to draw images in a 3D space, and then walk around those images to look at them from all sides — something that also won over acclaimed Disney animator Glen Keane.

The Gear VR, and other mobile VR solutions like Google’s Cardboard, offer none of these features. Instead, they just allow for rotational tracking, which means that they can keep track of users turning their head, but not moving within a 3D space. Some developers have tried to overcome these constraints with clever tricks. But overall, it has severely limited what developers can do with these headsets, and how consumers can experience immersion with them.

Why nobody has done this in mobile yet

The reason for Gear VR not offering positional tracking is twofold. First, the headset doesn’t ship with any kind of external tracking sensor like the ones included with the Oculus Rift and HTC Vive headsets. But sensors are only part of the puzzle.

To actually include the position and movements of users in a VR experience, developers have to rely on real-time rendering, something that requires a lot of computing power — which is why consumers will need a state-of-the-art $1,000 PC with a high-end graphics card to use the Oculus Rift.

Processing signals with minimal latency is especially important for these kind of experiences. Our brain expects immediate visual feedback when we turn our head or move our body to look around — even a delay of a few milliseconds can lead to nausea in VR.

Why a solution may be around the corner

That’s not to say that positional tracking is impossible for mobile VR headsets. Mobile phones get better and faster chipsets every year, and Samsung is expected to use a new chipset that it boasts will enable “highly immersive 3D gaming and life-like virtual reality experiences” for the Galaxy S7.

New chips like this could go a long way towards enabling positional tracking, but the company would still need to figure out a way to actually track users’ motions. That’s why a rumor from last fall that Samsung was adding dual cameras, capable of measuring depth, was so interesting.

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Of course, it’s also possible that Samsung could outsource tracking to the headset itself. That’s the strategy of Leap Motion, a company that originally developed a sensor for gesture tracking for laptops and PCs that is based on the combination of infrared and traditional cameras. Leap Motion just unveiled a new technology called Orion meant to bring motion tracking to VR headsets.

The company is looking to license Orion to VR headset makers to include into their hardware, and representatives have told reporters that it expects several companies to incorporate its technology into its headsets later this year. Leap Motion hasn’t named any partners yet, but the company’s CTO will coincidentally speak at Samsung’s developer conference in April.

What to expect from Samsung this weekend

Does that mean that Samsung will announce positional tracking for Gear VR this weekend? Not necessarily. The company may as well just boast the S7’s graphics processing power as ideal for VR, and enthusiasts may have read too much into a few seconds of promotional video.

But multiple VR industry insiders have told Variety that there is no doubt that Samsung is working on some kind of positional tracking. And when the company finally does introduce this technology, it may just be able to close the gap between mobile and stationary VR.