Elsewhere, would-be novelists got a new way to write as Lenovo launched AnyPen, which lets you write on a tablet with any ordinary pen or pencil. And LG unveiled a new curved smartphone. The International CES show in Las Vegas this week isn't typically a major forum for mobile products, as many manufacturers wait a month or two for the Mobile World Congress in Barcelona. But it's hard to separate mobile from other technologies these days.
Here are some highlights from the gadget show on Monday.
Toyota has been working on a hydrogen-powered car for some time. But now it's opened up its technologies to anyone, even its competitors, in the hopes of speeding the development of hydrogen-powered vehicles and their fueling stations.
Toyota executive Bob Carter compared Mirai's development to the gamble the company took on the electric Prius, which now has become a ubiquitous sight on most roads.
"We can speed the metabolism of everyone's research and development," he said.
Don't expect a rush of carmakers to line up, though. Quite a few have their own hydrogen fuel-cell cars in the works. But there's the quandary of the car and the fuel station. Which comes first?
"We cannot have the car without the refueling stations," he said.
Toyota's patents include 70 designs for hydrogen-refueling stations, the plans for which are also now royalty-free.
Carter says California is on its way to building 100 stations with some $200 million the state set aside. The carmaker offered one of the main station developers a $7.2 million loan for maintenance and operations and has partnered with another company to develop stations in New York, New Jersey, Massachusetts, Rhode Island and Connecticut.
Sometimes, it's easier to write or draw something than to type. Some tablets including Microsoft's Surface and Samsung's Note series come with styluses to do just that, but that means having an extra item to carry around and potentially lose.
Now you can write on a tablet screen with just an ordinary pen or pencil. Lenovo is introducing a technology called AnyPen in its new 8-inch (20-centimeter) Yoga Tablet 2. Lenovo says the pen or pencil will even make touchscreen navigation easier than using a finger.
The tablet is built to withstand normal pressure, but don't press too hard, or you might scratch the surface.
All in the screens
LG G Flex2 has a slightly curved screen, as the name implies. LG says that makes phones easier to hold and the display easier to read. Even more notable is the fact that LG is also making the Flex2 smaller than its predecessor, countering a trend toward bigger and bigger phones.
LG says it got complaints that the previous, 6-inch (15-centimeter) version felt too big. The new one will be just 5.5 inches (14 centimeters), which LG considers the "sweet spot" for smartphones. That's the same screen size as Apple's new iPhone 6 Plus (Review | Pictures), though it's actually slightly shorter when placed side by side.
LG is also making the back of its new phone "scratch-proof" by adding self-healing properties. Scratch or nick it under normal use, and the mark disappears in seconds. The screen itself isn't scratchproof, but LG says it's more durable than usual with a special chemical layer applied to Corning's Gorilla Glass.
The Flex2 has improved screen resolution over the original Flex, at 1080p high definition, though that's still behind LG G3 (Review | Pictures) in sharpness. The Flex2 also introduces some selfie features and a way to quickly check the time and notifications without turning the entire screen on.
Curved-screen phones remain a niche product, and LG doesn't expect to ship as many Flex2 phones as its flat G3 smartphone. A price hasn't been determined, but it's expected to be more than the G3 and other high-end phones, which typically cost $600 to $700 without a two-year contract.
Meanwhile, Sharp plans to release a 5-inch (12.5-centimeter) frameless phone - the screen goes right to the edge. It actually uses an optical-lens trick to make the front panel appear to extend to the edge. Magic or not, the trick keeps the overall phone smaller.
Virtual reality, real eating
Samsung has traditionally been known for its hardware - from TVs and appliances to phones and smartwatches. It's now making a bigger push into content.
The company paraded three leading chefs on stage - Michel Troisgros of Maison Troisgros in Roanne, France, Christopher Kostow of The Restaurant at Meadowood in California's Napa Valley and Daniel Boulud of New York City's Daniel - to launch an app with recipes and other content. The three chefs will share some of their favorites. Samsung will also make a Chef Collection edition of its tablet.
Meanwhile, Samsung is trying to make its new Gear VR virtual-reality headset more appealing by developing more content. The new Milk VR service will include updates of 360-degree free content five days a week. David Alpert, a producer for the hit AMC show "The Walking Dead," will create a mystery-suspense episodic thriller exclusively for the service. Virtual reality "allows us as storytellers to really push the boundaries and explore new ways of engaging the audience," says Alpert. Content will also come from the National Basketball Association and brands such as Mountain Dew.
Let's all get along
Many of the smart-home products out so far haven't been that smart in the sense they communicate only with their own app and products from the same manufacturer. That's starting to change.
AT&T, for instance, said its Digital Life home-security and automation system will soon work with products from Samsung, Qualcomm, LG and Lutron. AT&T's app, for instance, will be able to control Lutron window shades and Samsung's security cameras, while consumers will be able to see on the LG TV that someone is at the door.
AT&T officials say that such collaborations are needed to drive greater adoption.
Other companies are using CES to showcase compatibility with Google's Nest smart thermostat and Apple's HomeKit - two of the emerging hubs for controlling the smart home. That will allow a new Whirlpool dryer to run slower and save energy, for instance, when Nest senses that no one's home.