Samsung Electronics Co plans to introduce tablet computers this quarter based on Google's Android operating system, joining a growing list of firms seeking to challenge Apple's popular iPad.

Global handset vendors and PC makers including Nokia, LG Electronics and Hewlett-Packard Co are moving into the new category of devices, between traditional PCs and smartphones, taking a cue from Apple.

Samsung, the world's No.2 handset maker after Nokia, said its tablet PC will have a 7-inch display, smaller than the 9.7-inch screen on the iPad, which has sold more than 3 million units since its April launch.

It did not provide further details.

Its local rival LG Electronics, the world's No.3 handset maker, also plans to introduce tablets or slate devices running on Android in the fourth quarter.

Microsoft Corp said on Thursday it would introduce new tablets based on its Windows operating system soon to beat back advances by Apple and Google and is working with PC makers Acer Inc, Dell Inc, Toshiba Corp and others to develop the devices.

(Reporting by Miyoung Kim; Editing by Ken Wills)

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