US technology giant Hewlett-Packard rolled out its new TouchPad tablet computer on Friday, seeking to dethrone the dominant Apple iPad and revive its slumping fortunes.
The TouchPad went on sale in major US retailers such as Best Buy and Walmart as well as on Amazon.com, HP said in a statement.
It is expected to go on sale shortly in Britain, Ireland, France, Germany and Canada, and later this year it will become available in Italy, Spain, Australia, Hong Kong, New Zealand and Singapore.
Unlike the iPad, the TouchPad supports Adobe's Flash video format. It runs the webOS operating system, developed by Palm, the mobile-device pioneer that HP acquired last year for $1.2 billion.
The TouchPad debuted to mixed reviews, suggesting it will have difficulty challenging the iPad and its numerous imitators.
Last month, Apple said that it had sold 25 million iPads since releasing the first version of the device in April 2010. Apple released its next-generation iPad 2 in March.
Besides the iPad, the market for tablet computers now includes the Samsung Galaxy Tab, the BlackBerry PlayBook, the Motorola Xoom and dozens of devices running Google's Android operating system.
HP's stock has slumped 12 percent since the beginning of the year as many analysts have warned that the Palo Alto, California-based company is being overtaken by younger, nimbler rivals such as Apple and Dell.
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