Amid the thousands of iPhone and iPod Touch applications submitted that let users play games, listen to music, organize their lives, balance their check books and more, a few (4 percent, the company says) just don't pass muster.
Some get nixed because of content the company finds offensive, others because the purpose is too close to something Apple already has in the works.
The company doesn't often elaborate on its screening process (and declined to comment for this story). But it often leaves frustrated developers and controversial headlines in its wake.
Here are nine apps that ran into problems.
The most recent app to grab headlines, the 99 cent Baby Shaker, was pulled from the App Store Wednesday after it prompted outrage from organizations such as the National Center on Shaken Baby Syndrome and the Sarah Jane Brain Foundation.
The description of the app said, "See how long you can endure his or her adorable cries before you just have to find a way to quiet the baby down!"
The program displays a black and white picture of a baby with the sound of crying. Users shake the iPhone to stop the crying until Xs appear on the eyes of the baby. The company behind the app, Sikalosoft, did not immediately respond to requests for comment.
Apple offered an apology Thursday, the same day the App Store reached 1 billion downloads.
Apple spokeswoman Natalie Kerris said the game was "deeply offensive" and should not have been approved for sale, according to The Associated Press.
"We sincerely apologize for this mistake," Kerris said in a statement.
Before Apple yanked this $999.99 iPhone and iPod Touch application from the App Store in August, eight people had purchased the functionless application.
Designed by German developer Armin Heinrich, the program did nothing but broadcast to the world the wealth of the owner. Once downloaded and activated, "I Am Rich" displayed a glowing, red "ruby" on the user's iPhone screen.
In its official App Store description, the developer wrote: "The red icon on your iPhone or iPod Touch always reminds you (and others when you show it to them) that you were able to afford this. ... It's a work of art with no hidden function at all."
According to tech blog Valleywag, one curious patron accidentally downloaded the application, thinking it was a joke. But it seems that seven others -- five in the United States, one in Germany and one in France -- meant to actually buy the pricey program.
When another developer tried to spoof the "I Am Rich" app with a "poor man's version," Apple denied that one, too.
Submitted to Apple later in August, "I Am Poor" was intended to be the ultimate un-status symbol.
"It displays my artistic rendition of the poor college students standard meal -- ramen, mac & cheese, and tuna fish," Hardy Macia, the app's developer and owner of Canterbury, N.H.-based Catamount Software, wrote on his blog after getting Apple's rejection notice.
Apple told him it was turned down because it didn't contain any user-accessible functionality, he said.
Macia said he adapted the app in March so that it's now an E-Book of P.T. Barnum's "Art of Money Getting." But he's still waiting for word from Apple.