NEW YORK (FORTUNE) - A couple of years ago, when I'd ask wireless phone executives and analysts who in Hollywood "got" the whole idea of putting video content and other entertainment on mobile phones, almost everyone would offer some variation of the following answer: "Lucy Hood, of course."

Lucy Hood, of course, heads up Fox Mobile Entertainment, a unit of Rupert Murdoch's News Corp. media empire. And in just a few short years, Hood has pushed Fox to the forefront of producing content for the very, very small screen, reformatting existing television shows – her team coined the term "mobisode" – as well as creating original programming for cell phones.

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"At Fox, we like to be first," Hood said in a phone interview a few weeks ago.

Now, though, Hood is hearing footsteps. Rival media companies have answered phone companies' calls for more mobile content, offering up games, news clips, short cartoons and other cell-phone friendly fare. With their television and movie businesses facing declines, studios look at wireless devices and see dollar signs. (After all, ringtones have become a multibillion dollar business for the record companies.)

"Fox is raising the bar for everybody," says John Harrobin, vice president of marketing and digital media for Verizon Wireless, "and others are looking to outdo Fox and Lucy over the next year."

Hood has a few tools to keep her ahead of the pack. News Corp. operates globally, and Hood says she is able to draw from the company's experiences overseas, where consumer trends in wireless usually crop up first. For example, long before Americans were changing their ringtones every week, News Corp.'s BSkyB unit started seeing big demand for wireless screensavers and ringtones. "That gave us a heads up that consumers were really interested in this kind of content," she says.

But Hood's real secret weapon may be her instincts for translating traditional media content into the mobile world. Hood came up with the idea five years ago to let American Idol fans vote via wireless text messages. She remembers sitting in a meeting with her boss hashing out ways to use technology to promote the show in its first season.

"What people really love about this show is the ability to affect the outcome," she recalls telling Gail Berman, who is now president of Paramount Pictures. "We said, 'What if they could vote on their cell phones?'" It was, at the time, a novel idea, but one that showed an understanding of both the programming and the power of the cell phone.

Last season, Cingular Wireless – Fox's exclusive partner on text voting – reported 41.5 million American Idol-related messages. "I've been at this company for 16 years," Hood says. "I've worked in traditional media and have a lot of respect for it."

Like a lot of media executives working in wireless, Hood believes in wireless-specific programming. Her groundbreaking mobisode, "24: Conspiracy," seized on the popularity of the Fox television show, but presented viewers with an original story line, all in bite-sized pieces. (Though to some fans' dismay, Conspiracy didn't include protagonist Jack Bauer, the field agent played by Kiefer Sutherland.)

That doesn't mean Hood isn't willing to repurpose existing Fox content for the web. Her personal ringtone is an audio clip of a character from the Fox animated show "Family Guy," intoning: "Damn you, vile woman...your uppance will come."

The wireless carriers like Hood because she's serving up much needed content to fill the broadband wireless networks they've invested billions to build. In fact, they are so eager for more stuff for subscribers to download, that they encouraged Fox to launch Mobizzo, a mobile portal that aggregates different mobile-friendly games, music and exclusive, for consumers of the top four wireless operators to purchase directly from Fox.

Having a head start will surely help Hood as she tries to develop new content for wireless devices. Still, her lead isn't completely assured. Already some of the same people who told me to keep an eye on Hood are suggesting that GE's NBC Universal is poised to come on strong in wireless in the coming months. And dozens of upstarts have come on the scene, selling games and other diversions that are competing for screen time with Fox.

Hood doesn't seem like the type to let her guard down, but if she needs motivation, she might listen to her mobile-phone ringtone: if she's doesn't stay ahead of the competition, her uppance will come.