Mark Zuckerberg, chief executive officer of Facebook, speaks during an event in Menlo Park, California.

Mark Zuckerberg, chief executive officer of Facebook, speaks during an event in Menlo Park, California. Photo: Bloomberg

Facebook has unveiled a software suite which stakes out a "home" on Android smartphones as it steps up its challenge to Apple and Google in the booming mobile market.

Chief executive Mark Zuckerberg said on Thursday the new software weaves the social network into the home screen of HTC and Samsung phones powered by the latest versions of Android to focus experiences on "people and not apps".

A Facebook employee holds a phone that is running the new "Home" program during an event at Facebook headquarters.

A Facebook employee holds a phone that is running the new "Home" program during an event at Facebook headquarters. Photo: AFP

"Why do we need to go into those apps in the first place to see what's going on with those we care about?" Zuckerberg told a gathering at the company's headquarters in Silicon Valley.

"We're not building a phone and we're not building an operating system, but we are building something that's a lot deeper than an app," Zuckerberg said.

Facebook called the new software "a new way to turn your Android phone into a great, living, social phone".

Facebook's new Android app in "Chat Head Thread" mode.

How Facebook's new Android app will look.

The software, which allows users to see Facebook's "Cover Feed" when they turn on their phones, will be available for download from Google's online Play shop in the United States starting April 12, Zuckerberg said.

A version should be available in Australia in coming weeks, according to Facebook, which said it is in the process of tailoring "Home" for tablet computers.

Home will be available through Taiwan-based electronics firm HTC, which will launch its Facebook home-screen smartphone called HTC First, to be available through US telco AT&T at a price of $US100.

Facebook's new Android app in "Chat Head Preview" mode.

Facebook's new Android app.

"It is the only phone that has Facebook Home pre-loaded and optimised," HTC chief Peter Chou said while joining Zuckerberg at the event.

"Mobile is fundamentally social; it is all about connecting with other people," Chou continued. "This is a great opportunity to bring mobile and social together even closer."

Zuckerberg demonstrated how a user would start with Facebook on the home screen and be able to navigate and switch back and forth between apps, and simultaneously send and receive messages through "chat heads" which are overlaid on the screen.

For Facebook, bolstering its mobile presence is critical. Nearly 70 per cent of Facebook members used mobile devices such as smartphones and tablets to access its service at the end of 2012, and 157 million of Facebook's roughly 1 billion users accessed the service solely on a mobile device.

The company has stepped up efforts to ensure that its revenue-generating ads can be viewed on mobile devices and Zuckerberg has said that the company's engineers are now focused on creating "mobile-first experiences".

"I think this is a really big deal for Facebook," said Peter Corbett of the research firm iStrategyLabs.

"We've actually seen Facebook call themselves a mobile company recently and if you look at their analytics, more than half of their users are accessing Facebook through mobile. Now that they have what will essentially be a native branch of the Android operating system that they control and build upon, this is the future of Facebook."

Corbett added that "Apple should be worried to a certain extent" because Facebook will "put this in front of millions and millions of the world's youth who may decide 'I want a Facebook phone instead of an iPhone'".

Analyst Trip Chowdhry said the new software is a potentially "groundbreaking experience" which could help Facebook compete with Google in the market for mobile advertising.

"Since Facebook is not imitating, they will carve a leadership position," he said, adding that "Google missed a huge opportunity in social mobile phones".

Zuckerberg said features like Cover Feed will be ad-free initially, but he envisioned advertising as another form of content that will eventually be integrated. Analysts say the company treads cautiously when introducing ads into any of its services, wary of infuriating users.

"This is about becoming more deeply embedded in the operating system on mobile devices, and creating a broader platform," said Jan Dawson, chief telecoms analyst for the research firm Ovum. "It will allow Facebook to track more of a user's behavior on devices, and present more opportunities to serve up advertising."

But "that presents the biggest obstacle to success for this experiment: Facebook's objectives and users' are once again in conflict. Users don't want more advertising or tracking, and Facebook wants to do more of both".

Facebook customised Home for Android-powered smartphones because the operating system made available free by Google can be openly tweaked by hardware makers as opposed to the tight grip Apple keeps on iPhone innards.

Zuckerberg was careful not to throw down overt challenges to Apple or Google.

"We have a great relationship with Apple," Zuckerberg said.

"Google is aware of what we are doing; we have talked to them," he added. "We are committed to doing our best on every platform."

Zuckerberg reasoned that since people spend an average of 20 per cent of their smartphone time at Facebook, improving the experience on Android handsets was a good thing for Google's mobile operating system.

"Every company that I know wakes up in the morning trying to build the best experience; and Google does too," Zuckerberg said.

"In a way, this can start to bring some of those high quality experiences you see on iPhones to Android, and that could be really good for Android."

The announcement comes with Facebook trying to connect more with mobile users, and — importantly — deliver more ads in the fast-growing segment.

The research firm eMarketer said US mobile advertising spending grew 178 per cent last year to $US4.11 billion, a market that nearly tripled last year.

Google took more than half of those revenues, but Facebook's share in growing: eMarketer said the social network accounted for 9.5 per cent of mobile ad revenues in 2012 and is expected to take 13.2 per cent this year.

AFP and Reuters