When Apple first announced the App Store they intimated that the use of signed and DRM’d apps would allow Apple to protect the iPhone from malicious apps and they even suggested they would be able to deactivate such malicious apps remotely.

Author of iPhone Forensics, Jonathan Zdziarski, has revealed the URL Apple use to keep a list of the blacklisted iPhone applications as…

https://iphone-services.apple.com/clbl/unauthorizedApps

According to Zdziarski: “This suggests that the iPhone calls home once in a while to find out what applications it should turn off. At the moment, no apps have been blacklisted, but by all appearances, this has been added to disable applications that the user has already downloaded and paid for, if Apple so chooses to shut them down.

“I discovered this doing a forensic examination of an iPhone 3G. It appears to be tucked away in a configuration file deep inside CoreLocation.”

Basically what this means is that Apple can remove offending apps and it is possible that they could de-authorize the blacklisted application on already installed iPhone handsets.

Source — macrumors