Apple will continue dominating the Web tablet market until 2014, according to a new report from research firm Gartner.

The firm poured cold water on the prime challengers, saying Android tablets are selling slower than expected because of their shortcomings and Windows 8 tablets are too late to win over consumers.

Global tablet sales are on fire. Gartner predicted 63.6 million tablets will be sold this year, up 261 percent from the 17.6 million sold last year.

Growth will be strong through 2015, when the firm expects sales to reach 326.3 million units. By then, the line between Web tablets and PCs will blur as Windows-based tablets will be on the market, but Gartner's forecast blends both platforms.

Apple's share of the Web tablet market will fall about 10 percent this year, to 73 percent, but it will continue to hold more than 50 percent of the market share until 2014, the firm said.

Google's Android platform will account for 17.3 percent of the market this year, up slightly from its 14.3 percent share last year, the firm said.

Android's growth is slower than expected and Gartner lowered its growth forecast by 28 percent. It would have lowered it further if it weren't for strong sales of low-end tablets in Asia and expectations that Amazon.com will release an Android tablet this year.

"So far, Android's appeal in the tablet market has been constrained by high prices, weak user interface and limited tablet applications," analyst Carolina Milanesi said in the release.

Gartner's cool to the prospects of tablets based on Microsoft's upcoming Windows 8 operating system. It said buzz generated at the company's Build conference last week "might be short-lived if Microsoft's push to use the new OS across devices comes at a compromise in usability. Moreover, the late arrival might limit its appeal, especially to consumers, as Apple and Android will be more entrenched by then."

The firm sees the biggest opportunity for Windows 8 tablets in large copmanies where IT departments will like the way it works with other Microsoft products.

Research In Motion's new QNX platform is "promising" but it will be a challenge for RIM to attract app developers while it's under pressure to maintain its smartphone business, Gartner said.

A chart included with the release: