ABI Research said Tuesday that Apple's iPad highlights the "real start" of a tablet computer market that should grow more than tenfold to reach about 57 million devices sold annually by 2015.

"Apple's iPad is not the first media tablet," said ABI senior analyst Jeff Orr. "But it does help define this new device category."

The main focus of a media tablet is entertainment, according to the US-based market-tracking firm.

ABI defined the tablets as having touchscreen controls, wireless Internet connectivity, screens from five inches to 11 inches (12.7 cms to 27.94 cms) in size, and video and gaming capabilities.

"A tablet will not replace a laptop, netbook or mobile phone, but will remain an additional premium or luxury product for wealthy industrialized markets for at least several years," Orr said.

ABI predicted tablet computer makers will ship four million units this year.

Apple is expected to be a "fairly sizable player" in a tablet arena with traditional computer makers such as Lenovo and Hewlett-Packard as well as small firms such as Notion Ink.

The culture-changing California firm may have done all media tablet sellers "a favor" by raising the public profile of the devices with iPad hoopla, according to Orr.

Apple chief executive Steve Jobs hailed the iPad as a "revolutionary" device when he introduced it to the world on January 27 at an event in San Francisco.

Some technology analysts predict the iPad with its multimedia capabilities will be the best-selling electronics device in 2010.

Others question whether people will want to tote around what some called a notebook-sized iPhone without a phone.

Unveiling the iPad, Jobs admitted he was taking a gamble by trying to carve out an entirely new device category between the laptop computer and the smartphone.

"We think we've got the goods," Jobs said. "We think we've done it."

Users eager to judge for themselves will have to wait two months before the first iPads are shipped worldwide at an entry-level price of 499 dollars.