SAN JOSE, CA — A consumer group has sued Apple Computer Inc., alleging the iPod nano player is defective because its screen is easily scratched and that the company is breaking its product warranty by charging $25 for replacements.

The lawsuit by the Los Angeles-based Foundation for Taxpayer and Consumer Rights claims the pencil-thin nano introduced last fall cannot endure normal use without getting scratched to the point where it becomes unusable. The suit contends the Cupertino-based iPod maker should warn users accordingly.

The suit, which was filed Thursday in San Mateo County Superior Court, demands that Apple recall or repair the defective products for free, or refund the purchase price to dissatisfied customers. It also asks that the Apple add scratching or cracking to its warranty coverage.

Apple spokesman Tom Neumayr declined to comment Friday, citing company policy regarding pending litigation.

Apple has been hit with a string of consumer lawsuits over its widely popular iPod players. More than 30 million iPods were sold last year, bringing cumulative sales to 42 million units since the original product debuted in 2001.

The law firm behind the latest nano suit, Cotchett, Pitre, Simon & McCarthy of Burlingame, is seeking class-action certification to cover an unspecified number of affected consumers.

It is the same firm which won a settlement last August after alleging Apple failed to disclose the limitations of its older-model iPod batteries. Terms of that settlement ranged from Apple giving affected customers $25 in cash or credit to full battery replacements at no charge.

Other pending lawsuits against Apple include claims the iPod can cause hearing loss and a separate case by a different law firm alleging the design the iPod nano screen is inherently flawed.