PIC: Stephanie Pratt Bares Buns in PETA Ad

Credit: Courtesy of PETA

Stephanie Pratt is stripping for a good cause.

The Hills star, 24, poses totally nude (with just a pair of rabbits covering her breasts) for a new PETA iPhone app called "Be Nice to Bunnies," which lists products that aren't tested on animals.

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Apple deemed the app cover too risque, so she'll appear fully clothed on iPhones and nude in the print campaign.

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"I want to help consumers be informed and keep them compassionate," says Pratt of her decision to take it off.

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Khloe Kardashian, Eva Mendes, Alicia Silverstone and Pamela Anderson have also shed their clothes for the animal-rights group.