Random House Hires a Big Name in Fitness

Suzanne DeChillo/The New York Times David Zinczenko in his office at Men’s Health in 2010. He now operates his own company, Galvanized Media.

David Zinczenko, the former Rodale Press executive with a talent for self-promotion and sculpturing physiques, has signed on with Random House to provide some juice to its health and fitness offerings.

At the end of 2012, Mr. Zinczenko left his prominent positions as the editor of Men’s Health magazine and the general manager of Rodale’s Healthy Living Group and Rodale Books. Though his contract was up, he also had been clashing with Rodale’s owners, who found that his talent for being in the spotlight tended to detract from their brand, according to people in the publishing industry.

He then started his own company, Galvanized Media, with Stephen Perrine, another Rodale executive.

On Monday, Random House will announce that it has come to agreement with Mr. Zinczenko to give him his own imprint, distribution and multimillion-dollar book publishing deal with its Ballantine Bantam Dell division. Random House called the deal “unprecedented in scope” for that division.

As might be expected, Mr. Zinczenko has big plans for the imprint. “I anticipate we will swiftly branch out into books on overall health and wellness as well as self-help and even business and perhaps children,” he said in an interview by phone last week.

The first part of the deal is that Mr. Zinczenko, who has helped write best-selling health and fitness books including the “Eat This, Not That” series (which sold seven million copies in the North America) and “The Abs Diet,” will now write three yet-to-be-titled books on exercise, diet and nutrition for Ballantine. The first book will appear in 2014.

Mr. Zinczenko has also entered into a partnership with the Random House Publishing Group to form a new imprint â€" Zinc Ink â€" which will publish six to 12 general nonfiction and lifestyle books annually, beginning next year. He and the publishing house will share in profits.

Among the books the new imprint will announce Monday are “The EveryGirl’s Diet” by the best-selling author Maria Menounos, and “Sleekify” by the boxer and celebrity trainer Michael Olajide Jr.

Additionally, Random House will distribute books created and packaged by Galvanized in association with magazine publishers and other media clients. The first announced partner is American Media Inc., a publisher that owns Shape and Men’s Fitness. As distributor, Random House will keep a percentage of book sales.

Obama Has Lost Advantage Over G.O.P. on Economy

During the debate over the so-called fiscal cliff in December, public opinion surveys showed more Americans trusted President Obama than trusted Republicans in Congress when it came to handling the nation's economy. The New Year's Day deal to avoid going over the cliff, which included higher marginal tax rates on high earners - something Mr. Obama had campaigned on and lobbied for - was largely seen as a victory for the president.

But with more budget battles approaching, over raising the nation's borrowing limit and perhaps reaching a grand bargain, Mr. Obama's advantage over Congressional Republicans has all but vanished. Public approval of his handling of the economy has slipped, according to polls, and surveys now show that a roughly equal number of Americans favor Mr. Obama as favor Congressional Republicans on economic matters.

In December 2012 and January 2013, polls found that roughly half of Americans had more faith in Mr. Obama's economic stewardship, while just over a third of respondents said they had more faith in the economic stewardship of Congressional Republicans. Since December, however, Mr. Obama's standing has declined by roughly 10 percentage points, while Republicans in Congress have gained 4 or 5 percentage points.

Other pollsters, asking slightly different questions, have also found that the White House and Congressional Republicans are now on more equal fiscal footing. A Fox News poll conducted this week found when “it comes to handling the budget deficit,” 44 percent of registered voters agreed more with Mr. Obama, while 41 percent agreed more with Republicans.

A CNN poll conducted March 15 to 17 found that respondents were split in whom they preferred on handling of “the federal budget and the way the government raises and spends money,” 47 percent for Mr. Obama and 46 percent for Republicans.

The CNN poll had another worrying number for Mr. Obama. The last time a government shutdown was in the news, in September 2011, CNN found that 47 percent of respondents thought Republicans in Congress would be more responsible for a shutdown if it occurred. Just one-third of respondents said Mr. Obama would be to blame.

But CNN asked the question again in its mid-March survey and found that Mr. Obama's advantage was gone; 40 percent of respondents said they would blame Congressional Republicans for a government shutdown and 38 percent said they would blame Mr. Obama. (Threat of a near-term government shutdown was averted after the House of Representatives passed a stopgap bill financing the government through the end of the fiscal year.)

Mr. Obama's approval ratings on his handling of the economy over all have also dropped since their high-water mark in December and early January.

It is not clear what is causing the decline, but it doesn't seem to be the actual economy. There are increasing signs that the recovery is accelerating. Recent reports on jobs and housing have been unexpectedly strong. And all the while, the stock market has been bullish.

In addition, Gallup's consumer confidence index has improved, albeit in fits and starts. And other polls on the economy show that public sentiment is not great, but it hasn't degraded in recent months.

One theory holds that the fight over the automatic budget cuts contained in sequestration hurt Mr. Obama. Some political observers contend that the Obama administration overplayed its hand in the run-up to March 1, when the cuts began to go into effect.

Of course, the dip in Mr. Obama's approval ratings on the economy might simply be a reflection of an overall dip in Mr. Obama's popularity after a postelection bounce. The president's job approval ratings improved after he won re-election, but that postelection honeymoon appears to be ending (a bounce is, by definition, ephemeral). According to the RealClearPolitics average, Mr. Obama's net job approval is just 1 percentage point (48 percent approve and 47 percent disapprove). That's down from a high in mid-December of plus 12 percentage points (54 percent approved and 42 percent disapproved).

Just as his overall job approval appears to be falling back to where it hovered for most of 2012, public approval of Mr. Obama's economic stewardship may simply be regressing toward the mean. Polls testing the public's trust in Mr. Obama and Congressional Republicans on economic issues are largely back to where they were for much of 2011 and 2012.

As a result -  unless the polls shift again - neither Mr. Obama nor Congressional Republicans will be able to count on having a significant advantage in public support in upcoming budget fights.

Which Governors Are Most Vulnerable in 2014?

A lot can change before Election Day next year, when 36 states will vote for governor. But at this early stage - when decisions on whether to run or retire are considered and made - 10 of the 32 governors who are eligible to run for re-election have net negative approval ratings in their states.

The two most unpopular governors up for re-election in 2014 are Gov. Lincoln Chafee of Rhode Island, an independent, and Gov. Pat Quinn of Illinois, a Democrat. But the remaining eight governors with net negative job approval ratings are Republicans, including four who rode the Tea Party wave to power in blue and purple states in 2010 and now appear to be in some danger: Gov. Rick Scott of Florida, Gov. Tom Corbett of Pennsylvania, Gov. Paul LePage of Maine and Gov. Rick Snyder of Michigan.

The chart below includes the three most recent job approval polls for each incumbent eligible for re-election in 2014. (The four states where term limits prevent the governor from running again - Arizona, Maryland, Nebraska and Arkansas - and Massachusetts, where Gov. Deval Patrick has announced he will not seek another term, are not included.) Surveys conducted before 2012 are not figured into the averages.

In Rhode Island, just 28 percent of residents approve of the job performance of Mr. Chafee, their Republican-turned-independent governor. The chief reason for Mr. Chafee's troubles appears to be Rhode Island's dismal economy. The state is tied with California for the highest unemployment rate in the nation, at 9.8 percent.

According to reports, Mr. Chafee is considering becoming a Democrat. That might not help him much. Roughly half of Rhode Island voters are unaffiliated with either major party, and their political allegiances are often fickle. If the economy remains bad, Mr. Chafee will have difficulty winning their votes again.

Although Mr. Quinn is the second most unpopular governor up for re-election in 2014, he is a Democrat in deep blue Illinois. If he runs, he is still considered a favorite to win re-election: the Cook Political Report, Sabato's Crystal Ball and The Rothenberg Political Report rate the Illinois governor's race, respectively, as leaning Democratic, likely Democratic and likely Democratic.

In other words, being unpopular does not necessarily make an incumbent vulnerable to defeat. The eight other governors up for re-election in 2014 who are under water in their job approval ratings are Republicans, but four of those Republicans - Gov. Sam Brownback of Kansas, Gov. Nathan Deal of Georgia, Gov. Nikki Haley of South Carolina and Gov. Rick Perry of Texas - are in solidly Republican states and are likely to have an easier road to re-election if they run.

But the remaining four - Mr. Scott, Mr. Corbett, Mr. LePage and Mr. Snyder - lead states that were carried by President Obama in both 2008 and 2012. All were helped by favorable political winds in 2010 that no longer blow so hard.

Mr. Scott appears to be in the most trouble. A recent Quinnipiac survey showed former Gov. Charlie Crist, a Republican-turned-Democrat and a possible candidate in 2014, beating Mr. Scott, 50 percent to 34 percent.

Mr. Scott has been stocking up campaign contributions, but currently only 32 percent of voters say he deserves a second term.

Mr. Corbett is in a similar position. Sensing weakness, Pennsylvania Democrats are lining up to challenge him.

Both Pennsylvania and Florida are rated as “tossups” by the Cook, Rothenberg and Crystal Ball reports, the only states - along with Rhode Island - to be rated tossups in all three sets of ratings.

In Maine, Mr. LePage's best chance of winning re-election may be to repeat his 2010 route to victory: winning a three-way race where the left-leaning and moderate votes are split. A recent survey by the Pan Atlantic SMS Group showed Mr. LePage leading all three-way matchups but losing by eight percentage points to an independent, Eliot Cutler, in a two-way race.

Mr. Snyder is in a slightly less precarious position in Michigan. His net job approval rating is negative, but in the single digits. The Rothenberg report rates the race as a tossup, but Michigan is rated as leaning Republican by Sabato's Crystal Ball and as likely Republican by the Cook report. Part of the reason for Mr. Snyder's relative strength is the lack of significant opposition. No prominent Democrat has announced an intention to run, but if one did, Mr. Snyder's chances could certainly diminish.

Mr. Snyder, Mr. LePage, Mr. Corbett and Mr. Scott may find hope in the fortunes of another Republican governor of a swing state who was elected in 2010: Gov. John Kasich of Ohio. Mr. Kasich's job approval rating was in the 30s in 2011. As Ohio's economy turned around, so did Mr. Kasich's image. The percentage of Ohio residents who approved of his job performance climbed into the 40s in 2012, and recent surveys have shown his numbers rebounding into the 50s.

Those numbers do not guarantee that Mr. Kasich will be re-elected, but he is in much better shape than his Republican colleagues. Not surprisingly, an incumbent governor's job approval ratings have been shown to be strongly correlated with how constituents vote.

Madison Avenue Springs April Fool\'s Pranks Early

By now, it has become commonplace for marketers and advertising agencies to “front-run” holidays and big calendar events, starting their campaigns centered on Christmas, the Super Bowl or the back-to-school shopping season earlier each year.

For 2013, it seems, April Fool's Day can be added to that list, as waiting until April 1 to spring pranks on unsuspecting consumers becomes increasingly passé. The reason for the April Fool's front-running is the same as the reason for the front-running of other noted days: the ability of social media like Facebook, Twitter and YouTube to convey and amplify marketing messages.

For instance, two major marketers started their April Fool's jokes last week. (Or, officially, it ought to be said, seem to have started them, in that neither is talking about whether their announcements were the real deal or tomfoolery.)

One company, Procter & Gamble, along with several of its agencies, introduced a Web site, a video clip on YouTube and a Twitter hashtag for a new variety of Scope mouthwash called Scope Bacon, billed as the mouthwash “for breath that sizzles.”

Bacon-flavored mouthwash? Really? It appears that America must wait until Monday to find out if Procter is pulling its collective leg - or, perhaps, pulling on a pig's foot.

The other marketer, the American Eagle Outfitters retail chain, introduced what it described as a line of Skinny Skinny jeans for young men and women, billed as “our skinniest fit yet.”

But in a video clip on YouTube, the models appear to be wearing body paint rather than pants. And on the retailer's Web site, there are cans of paint labeled “Skinny Skinny,” in two colors, at the preposterous price of $49.95.

Again, American Eagle cautioned patience to those waiting for an explanation.

Some potential pranksters that pulled forward their mischief at least had the courtesy to label what they had planned as related to April Fool's Day. One was CBS, which issued a news release on Tuesday that the April 1 episodes of “The Price Is Right” and “Let's Make a Deal” would have April Fool's Day themes.

In other instances, April Fool's jokes were shared with reporters on Friday with the proviso that they be embargoed until Monday.

One example was a mock news release from the New York office of the Mother advertising agency, announcing that Mother New York had been named the “new agency of record” for the shadowy conspirators known as the Illuminati after the mysterious organization spent “nearly 237 years” with its previous agency.

(Maybe the release is real in that, as is the case with so many announcements about ad accounts changing hands, Mother New York omitted the name of the previous agency.)

Munchkin, a maker of products for babies and children, is to announce on Monday an imaginary product named Naughty Mouth soap, “to make your point when baby's language isn't the cleanest.” Flavors are to include lying liver and whining wasabi.

And the Professional Association of Diving Instructors is to announce on Monday an April Fool's addition to its offerings: scuba diving certification for dogs and cats.

Bravo Discusses Mixing Advertising With Its Shows

Charles Sykes/Bravo, via NBCU Photo Bank Anderson Davis, star of a new advertising campaign for Kraft dressings, appeared as the guest bartender on the Monday night episode of “Watch What Happens Live” with Andy Cohen on Bravo, an example of the network's new focus on branded-entertainment deals.

Anderson Davis is not among the stars of Bravo series that the channel likes to call “Bravolebrities.” Nonetheless, he was treated like one on Monday night during an episode of “Watch What Happens Live”: he served as the bartender; joked with the host, Andy Cohen; and even took off his shirt to reveal a toned upper body that would not be out of place on one of Bravo's “Real Housewives” shows.

Mr. Davis is an actor and model hired by the Kraft Foods Group and its advertising agency, Being Los Angeles, part of TBWA Worldwide, to play a character named the Zesty Guy in a new humorous campaign for Kraft dressings. As part of a sponsorship deal with Bravo, Mr. Davis appeared on “Watch What Happens Live” as well as in commercials that ran during the show and during other series on Bravo earlier on Monday night.

Such sponsorship agreements - known as branded entertainment, content marketing and native advertising - are becoming common on Bravo, part of the NBCUniversal Cable Entertainment division of NBCUniversal. And as the channel plans its programming lineup for 2013-14 during what is called the upfront season, more sponsorships that integrate advertising into shows are planned.

Bravo was one of three cable channels that made upfront presentations in New York on Tuesday. It was a coincidence that the other two, Aspire and Up, also had inspirational, affirmative names. (Or was it part of a pattern? After all, upfront presentations are intended to persuade marketers and agencies to consider buying commercial time.)

“We do like what we're seeing and hearing from our advertiser partners,” Dan Lovinger, executive vice president for cable ad sales at NBCUniversal, said in an interview after the Bravo presentation. “Content development is exciting to a lot of brands,” he added, “because they're trying to find ways to populate social media sites and do social media outreach.”

Content marketing deals “require a lot of commitment from both sides,” Mr. Lovinger said, because of the additional work needed to integrate brands or products into shows in ways “that make sense.”

“What's most important is that the content flows, and makes sense, for the viewer,” he said, “helping to tell the story of the episode.”

Asked if it was easier to incorporate products or brands into Bravo shows because they are unscripted, Mr. Lovinger said it was, adding that the shows benefited from “dealing with a passion” among viewers like food or fashion.

As a result, he said, “we typically know whether a brand would resonate with a viewer” if it was to be interwoven into the plot of an episode of a show.

For the 2013-14 season, according to Bravo executives at the presentations - including Mr. Cohen, who is also the channel's executive vice president for development and talent - Bravo intends to increase significantly the amount of original programming being offered viewers, joining many other channels in beefing up their schedules to generate higher ratings from viewers and ad revenue from marketers.

There will be 15 percent more original programming on the channel in the coming season than there has been during the 2012-13 season. Last year, Mr. Lovinger said, Bravo added 126 new marketers to its list of advertisers on cable and 34 new marketers to its list of advertisers online at bravotv.com.

Bravo is adding 17 series to its lineup, all in the unscripted or reality genre, joining 18 unscripted series that will return for the coming season. There are three additional unscripted series that are in development.

Of the new and potential unscripted shows at Bravo, there were plenty of larger-than-life real people who appeared to be candidates for Bravolebrity status. Among the clips that were shown during the presentation were residents of Charleston, S.C., who display, as one put it, “a certain high regard to leisure”; a divorce mediator; parents who follow “extreme” styles of raising their children; and residents of Long Island who go by the nickname “princesses.”

Also in development, said Jerry Leo, executive vice president for program strategy and production, are three scripted series; one of them, called “High and Low,” is set during the 1980s. A pilot for a fourth possible scripted series - a drama, “Rita,” featuring Anna Gunn of the AMC series “Breaking Bad” - is to be filmed next week.

Bravo plans an upfront party on Wednesday night for Madison Avenue that will include as guests more than 75 Bravolebrities, said Frances Berwick, president of the Bravo and Style Media division of NBCUniversal Cable Entertainment.

In addition to Mr. Cohen, they will include Jeff Lewis, a star of two Bravo series, “Flipping Out” and “Interior Therapy With Jeff Lewis.” Mr. Lewis was also on hand at the presentation on Tuesday morning, introducing Ms. Berwick and taking pokes at two stars from the “Real Housewives” franchise, Adrienne Maloof and Jill Zarin.

The two other cable channels that presented on Monday night, Aspire and Up (known until June 1 as GMC TV, and previously the Gospel Music Channel), do not plan an upfront party.

Instead, executives are in New York through Thursday to meet with agency executives and reporters on an Upfront Bus, which is decorated with the two channels' logos and stars of their shows.

On Tuesday, the bus was parked on 40th Street between Fifth and Sixth Avenues, next to Bryant Park. The next stops for the bus include Cincinnati, Detroit, Minneapolis and St. Louis.

For 2013-14, Up and Aspire plan to add unscripted reality series to their schedules. The programs will have an uplifting, family-friendly vibe decidedly different from the frank, adult attitude of the unscripted fare on Bravo.

The unscripted reality genre “doesn't have to be salacious, doesn't have to be a freak show, doesn't have to be a train wreck,” said Brad Siegel, vice chairman at Aspire and Up.

There are two unscripted series planned for Up. One is “Family Addition With Leigh Anne Tuohy,” the woman who was played by Sandra Bullock in the film “The Blind Side.” It will focus on helping expand the homes of families who are adopting foster children.

The other new unscripted series on Up will be “Bulloch Family Ranch,” about a family in Florida that offers troubled teenagers what is described as a “last second chance.”

Aspire has an unscripted series planned for 2013-14 titled “U.N.C.F.: The Next Generation,” about students assisted by the United Negro College Fund.

Like Bravo, Up and Aspire are expecting to sign additional content marketing deals with advertisers, said Mr. Siegel and Mary Jeanne Cavanagh, executive vice president for advertising sales at the channels.

For instance, they played a clip from “Bulloch Family Ranch” in which Rusty Bulloch delivers some nice words about a sponsor, Angel Soft bathroom tissue.

The busy week for upfront presentations continues on Wednesday with a presentation by the Weather Company, owner of the Weather Channel. On Thursday, Discovery Communications will host its presentation.

Those scheduled for next week include GSN, IFC and Syfy.

Stuart Elliott has been the advertising columnist at The New York Times since 1991. Follow @stuartenyt on Twitter and sign up for In Advertising, his weekly e-mail newsletter.

This post has been revised to reflect the following correction:

Correction: April 3, 2013

An earlier version of the post misstated the advertising agency responsible for creating the Zesty Guy campaign for the Kraft Foods Group. It is Being Los Angeles, part of TBWA Worldwide, not TBWA/Chiat/Day Los Angeles.

Al Jazeera Hires First Anchor for New U.S. Channel

Al Jazeera on Thursday hired its first new anchor, Ali Velshi of CNN, for its forthcoming cable channel in the United States, and confirmed that the channel would be called Al Jazeera America.

Mr. Velshi, currently the chief business correspondent and an anchor for CNN, will host a half-hour business program in prime time once the new channel replaces Current TV. Neither he nor a spokesman for the channel said they knew exactly when the channel would start, but the transition is expected to happen later this year.

Mr. Velshi said in a telephone interview that he “was really struck by their commitment to building a strong news organization.” When asked whether he was concerned about aligning himself with the Al Jazeera brand name, he indicated that he was not.

“I think the product will trump any preconceived notions that people may have going into it,” he said. “They're very determined for this brand to make an impact and for this brand to be a meaningful provider of news.”

In many parts of the world Al Jazeera, owned by the emir of Qatar, is already a force to be reckoned with. The Al Jazeera Media Network operates Arabic and English-language international news channels as well as a growing number of niche channels. But in the United States it has very little viewership because cable and satellite companies have, for the most part, declined to carry its channels.

In January, Al Jazeera bought its way into the country by acquiring Current TV, the channel co-founded by former Vice President Al Gore, for an estimated $500 million.

Al Jazeera opted not to use the channel space to simulcast Al Jazeera English; instead, it announced that it would set up a new channel specifically for the United States, with newscasts originating from New York, Washington and Los Angeles. It said that the tentative name was Al Jazeera America, and seemed to confirm that on Thursday by setting up promotional accounts for the channel on Facebook, Twitter and Tumblr.

“Over the coming weeks, we'll be making announcements about talent, programming and bureau locations across the United States,” the channel's announcement on Tumblr stated.

Mr. Velshi is the first boldface name to be announced. He said he anticipated others would be announced soon, but did not know who because his talks with the channel took place in secret. Referring to Al Jazeera's public estimate that it received 18,000 job applications for the 170 positions it advertised last winter, he said, “This is the first big journalism hiring binge that anyone's been on for a long time.”

Mr. Velshi's plan to leave CNN was announced internally earlier this week. He has spent the last 12 years at the network, initially as an anchor for the now-defunct business news channel CNNfn. He was a fixture on CNN during the financial crisis in 2008; more recently he tried his hand at morning and evening anchoring, but was passed over for permanent positions at either time of day.

For the past year he has anchored a daily newscast, “World Business Today,” for CNN's international news channel, and a weekly personal finance program, “Your Money,” for CNN's flagship American channel.

Jeff Zucker, the new president of CNN Worldwide, has been making sweeping changes to the flagship channel lately, but Mr. Velshi indicated that he was leaving of his own volition.

He said he was content at CNN, but as an anchor and correspondent there, “you're limited because it's a big company.” Al Jazeera America, on the other hand, is something that “we're starting from scratch.”

“I wanted to be somewhere where there's a real challenge to build the audience, to build the infrastructure, the whole thing,” he said.

Al Jazeera said in a news release that Mr. Velshi's half-hour program would have a magazine format. It will initially begin as a weekly program, but “is expected to move to a five-days-a-week schedule by year's end,” the channel said.

Ehab al-Shihabi, the executive director of Al Jazeera international operations, said in a statement, “We are thrilled to secure Ali's extraordinary talents and services. Al Jazeera America will be bringing respected, independent reporting to its viewers and that's exactly the type of coverage Ali Velshi is known for.”

Representatives of Al Jazeera have previously said that they expect the new channel to be available in roughly 40 million homes in the United States when it has its premiere. About 100 million homes subscribe to cable or satellite service.

Facebook\'s Play for the Smartphone Screen

9:20 p.m. | Updated Added more details and analysis.

MENLO PARK, Calif. - Cellphones have long been Facebook's Achilles' heel. With its users flocking to mobile phones by the millions - and many of its newest users never accessing the services on computers at all - the company has struggled to catch up to them.

On Thursday, Facebook unveiled its latest, most ambitious effort to crack the challenge: a package of mobile software called Facebook Home that is designed to draw more users and nudge them to be more active on the social network.

The new suite of applications effectively turns the Facebook news feed into the screen saver of a smartphone, updating it constantly and seamlessly with Facebook posts and messages.

.nytint-voicebox-title { text-transform: none !important; font-size: 1.1em; font-family: Arial, Helvetica, sans-serif; color: #333; } .nytint-voicebox-next-button { background-image: url(http://graphics8.nytimes.com/projects/assets/voicebox/stepper-right-on.png); } .nytint-voicebox-slide { width: 190px !important } #nytint-homepage-container { width: 190px !important } .nytint-homepage-container-slides { width: 190px !important } .nytint-voicebox-tweet { width: 190px !important } .nytint-voicebox-tweet-text { width: 190px !important; font-size: 13px !important; line-height: 17px !important; } #nytint-voicebox-wrapper { width: 190px !important; height: 150px; }

In so doing, Facebook has cleverly, perhaps also dangerously, exploited technology owned by one of its leading rivals, Google. Facebook Home works on Google's Android operating system, which has become the most popular underlying software for smartphones in the world.

The Facebook News Feed appears as soon as the phone is turned on. Pictures take up most of the real estate, with each news feed entry scrolling by like a slide show. Messages and notifications pop up on the home page. To “like” something requires no more than two taps. Facebook apps are within easy reach, making the phone essentially synonymous with the Facebook ecosystem.

“Today, our phones are designed around apps, not people,” said Mark Zuckerberg, Facebook's chief executive, at a news conference here at the company's headquarters. “We want to flip that around.”

Facebook Home will be available for download from Google's app store, Play, on April 12 for four popular, moderately priced phones that use Android and are made by HTC and Samsung. A fifth one, a new model called the HTC First, will be sold by AT&T for $100 with the software already loaded.

For the time being, Facebook will not show ads on the phone's home screen, which Facebook is calling Cover Feed. Since advertising revenue is crucial to the company's finances, however, it will almost certainly display ads there in the future.

Facebook Home is also clearly designed to get Facebook users to return to their news feeds even more frequently than they do now. Every time they glance at their phone at the supermarket checkout line or on the bus to work, they will, in essence, be looking at their Facebook page.

“It's going to convert idle moments to Facebook moments,” said Chris Silva, a mobile industry analyst with the Altimeter Group. “I'm ‘liking' things, I'm messaging people, and when ads roll out, I'm interacting with them and letting Facebook monetize me as a user.”

Krishna Subramanian, the chief marketing officer at Velti, a San Francisco-based company that buys targeted advertisements online on behalf of brands, pointed out that even without showing ads on the mobile cover feed, Facebook Home could prove to be a lucrative tool.

By nudging its users to do more on the social network, he said, the company will inevitably get “an explosion of mobile data that can be tied back into desktop advertising” to Facebook users.

A majority of Facebook's one billion-plus users log in on their cellphones. Most Americans now have an Internet-enabled phone, and smartphone penetration is growing especially fast in emerging market countries, where Facebook has substantial blocs of its users.

At Thursday's press event, Mr. Zuckerberg repeatedly signaled that he wanted the new product to enable a mass, global audience to connect to Facebook, especially those have yet to get on the Internet. “We want to build something that's accessible to everyone,” he said.

Although HTC is rolling out the first new phone with Facebook Home installed, and AT&T has agreed to sell it, other phone makers and carriers may be reluctant to load the software.

Jan Dawson, a telecom analyst at Ovum, said that Apple's iPhone and many Android smartphones already do a good job of integrating the Facebook application into their phones. And he said phone carriers were unlikely to give a Facebook phone made by HTC much support because the Taiwanese phone maker's past attempt at a Facebook phone - the ChaCha, which had a physical button for posting photos on Facebook - sold poorly.

“HTC may be desperate enough to do this, but carriers aren't likely to promote it heavily,” Mr. Dawson said. “As a gimmick, it may bring customers into stores, but they'll mostly end up buying something else.”

At Facebook headquarters Thursday, HTC's chief executive, Peter Chou, showed off a model of his new Facebook phone, called HTC First, in lipstick red. “HTC First is the ultimate social phone,” he said. “It combines the new Facebook Home and great HTC design.”

Whether consumers will embrace a phone that emphasizes Facebook over everything else also remains to be seen. Some are likely to have concerns about how much personal information they are being asked to share with Facebook. Additionally, checking Facebook dozens of times every day could result in hefty data use charges, unless users are connected to a Wi-Fi network or negotiate special packages with carriers.

Facebook and AT&T executives said they had taken that into account. Users will be notified when they are about to reach their data limits. The software can also be set to download data-heavy content like video only when the user is connected to a Wi-Fi network, and then save it in its memory.

The software's most powerful feature is to turn the cellphone into a starkly personal gadget.

Facebook employees, current and past, were invited to the product announcement, a sign of how crucial it has been for Facebook to crack the mobile puzzle. Silicon Valley has whispered for months about the prospects of a Facebook phone. Mr. Zuckerberg has consistently denied building one.

Thursday's announcement signaled that Facebook had stopped short of even building an operating system. Instead, it had simply altered its rival Google's technology.

The Android platform, Mr. Zuckerberg said, was built to be open to new integrations. Asked at the news conference whether he feared that Google executives would change their mind about Facebook using it to advance its mobile aims, he turned somewhat testy.

“Anything can change in the future,” he said. “We think Google takes its commitment to openness very seriously.”

Google, for its part, was notably genteel. “This latest collaboration demonstrates the openness and flexibility that has made Android so popular,” the company said in an e-mailed statement. “And it's a win for users who want a customized Facebook experience from Google Play - the heart of the Android ecosystem - along with their favorite Google services like Gmail, Search and Google Maps.”

Brian X. Chen contributed reporting.

A version of this article appeared in print on 04/05/2013, on page B1 of the NewYork edition with the headline: Facebook Software Puts It Front and Center on Android Phones.