After four days of confusion and adolescent hand-wringing, Apple (AAPL) finally spoke out about the change of policy that has removed thousands of risqué applications from its iPhone App Store.

The response came in an interview that senior vice president Phil Schiller gave Jenna Wortham of the
New York Times
.

Over the last few weeks, he told Wortham, a small number of developers had been submitting “an increasing number of apps containing very objectionable content.”

“It came to the point where we were getting customer complaints from women who found the content getting too degrading and objectionable, as well as parents who were upset with what their kids were able to see,” Mr. Schiller said.

The extent of the purge can be seen in a bar graph produced by AppShopper.com, which tracks the number of applications added and removed from the store each day. It shows Apple withdrawing more than 6,000 apps over the space of four days, including nearly 4,000 apps last Thursday alone.

“At the end of the day, Apple has a brand to maintain,” Piper Jaffray’s Gene Munster, told the Times. “And the bottom line is they want that image to be squeaky clean.”

Munster linked the purge to the release of the iPad tablet computer next month, which Apple plans to market for home and school use. But neither he nor Schiller could satisfactorily explain why thousands of apps showing bikini clad women were removed, while Playboy and the Sports Illustrated swimsuit edition were permitted to stay.

When asked about the Sports Illustrated app, Mr. Schiller told the Times that Apple considered the source.

“The difference is this is a well-known company with previously published material available broadly in a well-accepted format,” he said.

That was not an explanation that sat well with commentators writing for less well-known publications on the Web. See here.

[Follow Philip Elmer-DeWitt on Twitter @philiped]