Barnes & Noble is turning a page on its Nook business.

The New York-based bookseller said it would quit making its own color tablets as the digital business continued to produce red ink.

The company has been sinking money into its Nook unit in an effort to keep pace with readers' shift to digital media. But the device's popularity began tapering off around the holidays amid stiff competition from Amazon's Kindle Fire and Apple's iPad.

Barnes & Noble said it would shift manufacturing of its color Nook tablet to an as-yet unnamed third party. It still plans to produce its black-and-white e-readers.

The Nook unit's revenue sank 34% to $108 million in the fiscal fourth quarter, as the company's net loss more than doubled to about $119 million.

The company's sales of digital content also tumbled 9%. Barnes & Noble blamed the slide on tough comparisons to last year, when readers snapped up the "The Hunger Games" and "Fifty Shades of Grey" trilogies.

Still, the drop in content sales left Barclays analyst Alan Rifkin "highly disappointed," he wrote in a research note.

"It shows that a former avenue of sales growth for the company is no longer helping to drive revenues," Rifkin wrote.

Sales at its traditional book stores slumped, too, although that was somewhat offset by strength at its college bookstore chain.

Barnes & Noble shares sank 17%, its biggest drop in nearly two years, to $15.61. They had climbed 25% this year through Monday.

With News Wire Services

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