Answer: Virtual reality headsets.

Both companies used this year’s Mobile World Congress to announce several new flagship smartphones. But unlike previous years, each threw in a goofy-looking headset capable of virtually teleporting you into another world.

HTC announced the Vive, a product that’s received high praise from the show floor in Barcelona. For its part, Samsung announced the second-generation Gear VR Innovator Edition.

Neither company is going it alone. HTC partnered with Valve, the company behind the Steam online gaming platform. For the second time, Samsung has partnered with Facebook-owned mainstay Oculus VR.

Both products create an immersive experience through different approaches.

The Vive will require a connection to a nearby computer, similar to how the Oculus Rift operates. It’s far from mobile, though I doubt anyone would want to actually walk around in public while wearing it. The Vive is equipped with one high-definition screen in front of each eye, three sensors for tracking movement, and a pair of base stations to track your movement within a small room allowing you to actually walk around and explore your virtual environment.

Samsung’s Gear VR is designed to work exclusively with its Galaxy S6 and S6 Edge smartphones. In other words, the company’s flagship smartphone combo doubles as the screen and brains that run its VR headset. Controls are located on the side of the headset in the form of a series of buttons and a trackpad.

My experience with today’s virtual reality headsets is admittedly limited. I’ve used the original Gear VR with a Note 4 during the Consumer Electronics Show and I’ve experimented with Google’s Cardboard product. When I tried the Gear VR, I was asked to sit in a chair that was tucked away into the corner of a crowded, noisy booth with fellow attendees all gawking at those wearing the contraption. After I put it on, I found myself inside a virtual movie theater with a clip of a science-fiction movie playing on its giant screen. It took about 30 seconds to forget where I truly was—the Las Vegas Convention Center during one of the most well-attended technology conferences on the planet. Instead, my brain was convinced I had rented out an entire cinema to view a movie by myself. It was lonely, yet comforting.

One problem, though: When I removed the Gear VR, I felt nauseous. Motion sickness is something that’s plagued me my entire life, and it’s something a lot of people experience after using a VR headset. For better or worse, VR is, for me, synonymous with getting sick.

HTC claims to have solved this issue, claiming that “zero percent” of users feeling sick after using its Vive. That’s a bold claim, and one I’m naturally skeptical of. But I haven’t had a chance to try it out myself. Consumers will get to test the claim this holiday season, though an exact sale date or pricing details were, unfortunately, left out of the announcement.

As for the new Gear VR, Samsung has yet to announce details pertaining to its availability. (Though it’s safe to assume it’ll be available around the same time the Galaxy S6 products launch on April 10.) The previous version of the headset was priced at $199; it’s reasonable to expect a similar price for the new model. It should be noted that Samsung positions its Gear VR as an early adopter product that’s not meant to gain the traction a full-on consumer product, while Oculus has announced plans to release its first consumer product by the end of the year in partnership with Samsung.

Like any new device and ecosystem, pricing and content will drive consumer adoption of the latest generation of virtual reality systems. Which means developers must come up with more than a series of games and a virtual movie theater to convince me (and the world) that VR is a worthy purchase.

More coverage from Mobile World Congress 2015:

How Google’s Project Nova could upend the wireless industry

How Samsung’s new Galaxy S6 smartphones are like Apple’s iPhone 6

Jason Cipriani is the author of “Logged In,” Fortune’s personal technology column.