LAS VEGAS—Is Firefox OS growing up? I can't tell if Japan's weird new see-through Fx0 phone is the potential future of the low-cost smartphone OS, or just a novelty. It sure is neat, though.

The Fx0 is made by LG, and it's sold exclusively by KDDI in Japan. It was designed by Tokujin Yoshioka, a famous Japanese designer who's best known for working with Swarovski and Issey Miyake. He uses a lot of translucency, crystals and light in his work, and the Fx0 fits in perfectly.

The Fx0 is entirely made of translucent, textured amber plastic. You can see the battery and SIM/MicroSD card slots through the back, and the Au and Fx0 logos are visible through the side. The physical home button has a subtle Firefox logo on it. The whole thing is a very fun vareity of textures—patterned on the back, slightly ridged along the edges—so it's a lot of fun to fidget with.

With a 1.2GHz Qualcomm Snapdragon 400 processor and Firefox OS 2.0, performance is much, much better than the older, more sluggish low-end phones that have marked Firefox OS so far. While page load times were stalled by a slow Wi-Fi network, scrolling and pinch-to-zoom had finally shaken free of the jerkiness and pauses I'd seen on first- and second-generation Firefox phones.

Firefox OS 2.0 has a few new tricks. The home screen scrolls down vertically. You can alter the home screen icon layout so it's either a 4x4 grid or a 3x3 grid of even larger, more colorful icons, which look great on the 4.7-inch, 720p LCD screen. You can also now more easily flip through recently used apps, just by swiping left across the screen.

Recommended by Our Editors

Motorola Crams 2-Day Battery Life Into an Impressively Thin Edge

Apple WWDC 2026: How to Watch and What to Expect, Including iOS 27, Siri Updates, and More

Surprise! Apple Just Boosted Trade-In Values. Here's How to Prep Your iPhone to Get the Max Payout

Mozilla rewrote a lot of the built-in apps, too; the camera has much better autofocus, and the email, calendar, and clock apps all have new designs. According to KDDI, you can turn multiple Fx0 phones into a mesh network by tapping them together, which is pretty cool.

I'm not sure what the Fx0 is trying to accomplish, but I like the design. Until now, Mozilla has positioned Firefox OS as a way to get inexpensive smartphones into the hands of developing-world consumers. Developed-world phone buyers who can afford more, so far, have by and large wanted the third-party app libraries you find on Android and Apple phones.

But the "art project" aspect of the Fx0 is really compelling. Perhaps this is the "Nexus" of the Firefox OS realm - the phone for developers to carry, so they can write the Web apps that the "next billion" will use.