A video wall measuring 10 x 6 meters is unveiled during a news conference at McCarran International Airport in Las Vegas, Nevada, on Monday ahead of the International Consumer Electronics Show, which begins tomorrow. The video wall by Samsung Electronics is believed to be the largest in a United States airport, according to a media release.

Apple Inc's popular iPad is getting its strongest competition thus far as consumer-electronics manufacturers unveil tablet computers with bigger screens, front-facing cameras for video chatting and more.

The iPad has been a smashing success since its April launch, leaving other companies to play catch-up in the suddenly hot market for the keyboardless, touch-screen devices. Rivals are making a bigger push at this week's International Consumer Electronics Show (CES) in Las Vegas, betting they can challenge Apple with such features as Android, the popular smartphone software Google Inc developed to compete with the iPhone; high-definition touch screens and cameras for video chatting and taking photos.

The competition is going to be fierce. DisplaySearch analyst Richard Semenza estimated that a hundred different tablet models are in development, though not all of them will reach store shelves.

Major firms, including Motorola Inc and Dell Inc, are expected to trot out new models. At least two companies - high-definition TV makers Vizio Inc and AOC - announced tablets on Monday, days before the show's official opening tomorrow.

Toshiba Corp also plans to unveil one this week. Tentatively called the Toshiba Tablet, it will include two cameras for video chatting and taking photos, a high-definition screen that is larger than the iPad's and the upcoming Honeycomb version of Android that is optimized for tablets.

"This is the starting gun for tablets, except Apple had a yearlong lead in the race," according to BGC analyst Colin Gillis.

Apple was expected to sell more than 13 million iPads in 2010, making up the vast majority of the total market. Although analysts believe the iPad will still account for the bulk of the 55 million tablets that Gartner Inc expects will be shipped, there's still room for rivals to vie for sales of the remaining 10 million to 15 million devices.

Difficult inroads

It is going to be difficult for tablet makers and software providers to make inroads, though, given the iPad's name recognition and the hundreds of thousands of apps available for it in Apple's iTunes Store.

Android's growing popularity among smartphone users could give tablets that run Google's system a leg up, particularly once Honeycomb is made available.

Google has said little about Honeycomb, other than the fact that it will allow applications to present information differently depending on whether they're running on a phone or a tablet.

For example, Gmail on the tablet shows a list of e-mails in one column and the body of the one you're reading in a second column. On an Android phone, you'd only see one column at a time.

Honeycomb is thought to be the operating system of choice on several devices expected to make an appearance at the gadget show.

One is Toshiba's tablet, which the company said it plans to start selling by the end of June. A price has not yet been set, but the company believes it will be competitive with the iPad, which costs US$499 to US$829, depending on its memory capacity and wireless capabilities.

Handset maker Motorola is also expected to reveal a Honeycomb-based tablet, as it has hinted through the release of an animated video on YouTube last month called "Tablet Evolution presented by Motorola." The video showed various tablets throughout history, ranging from an Egyptian hieroglyphic-laden slab to the iPad and Samsung Electronics Co's Galaxy Tab. It then focused on a black podium emblazoned with Motorola's "M" logo that supported a mysterious covered object - presumably its own entry into the field.

A buzzing bee at the end of the video suggests that this may be the same Honeycomb-based tablet that Google's top mobile executive, Andy Rubin, showed off at a December conference.

With so many companies making Android tablets, electronics makers will need innovative hardware or a super-low price to stand out from the noise, said Gillis.

"At CES, the noise is going to get extremely loud," he said.