By Sven Grundberg

BARCELONA--Samsung Electronics Co. (005930.SE) Sunday brought yet another product into the increasingly crowded market of tablet computers, stepping up its efforts to compete with Apple Inc.'s (APPL) hugely successful line-up of iPads.

On the eve of the Mobile World Congress, which starts in Barcelona Monday, the South Korean company launched its eight-inch tablet, called the Galaxy Note 8, which it will start to sell globally in the second quarter of this year. The device, which runs the latest version of Google Inc.'s (GOOG) Android operating system and comes with a stylus pen, will compete directly with Apple's 7.9-inch iPad Mini, which the U.S. technology giant started selling in October last year.

In recent months, Apple's rivals have been releasing a flood of tablets powered by Google's Android operating system, as well as Microsoft Corp.'s (MSFT) Windows 8 software that is designed to work with touch screens. The iPad Mini was launched as a counteroffensive, amid intensified efforts to dominate the tablet market pioneered by Apple.

Samsung already sells a wide array of tablets, including the seven-inch screen Galaxy Tab 7.0, as well as several tablets with screen sizes around 10 inches, such as the Note 10.1 and the Nexus 10 that it constructed in close cooperation with Google.

Additionally, the company's Galaxy Note 2 device, which has a 5.5-inch screen, is a hybrid between a tablet and a smartphone, belonging to a category of products dubbed "phablets."

Despite its already large offering of tablets and super-sized smartphones, the South Korean company appears to expect the eight-inch tablet will become a vital part of its product portfolio. The company said the new Galaxy Note 8.0 will bring "fresh life into the [tablet] category" and that the device brings a perfect mix of "portability and everyday productivity."

While having made great strides with its range of Android-running Galaxy smartphones in recent years, Samsung hasn't been as successful with its push into the tablet market.

According to data from Strategy Analytics, a technology market research firm, Apple maintained its strong leadership of the tablet market last year, despite the launch of dozens of new Android models by numerous brands, such as Amazon.com Inc. (AMZN), Samsung and Asus (2357.TW).

Strategy Analytics estimates that Apple had a 58% market share of the global tablet market in the fourth quarter last year, measured by shipments, while tablets running Android had a 39% market share. A persistent problem for Android tablets is the few number of tablet-applications available for Google's software platform.

Write to Sven Grundberg at sven.grundberg@dowjones.com

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