Q:

Is it possible to change the Info.plist from another app?

I am trying to writing a patching app, where you would drop an app into the window and it would patch it. I was able to use NSDraggingDestination to retrieve the file path to the app that was being dropped and I was able to read and change the Info.plist. 
However when I try to write the altered Info.plist back to the app, it doesn't let me do so. Are there any tricks or is this just a security issue?

A:

Editing the .plist breaks the signature of the app. On iOS this would make the app unable to run. You can read more about code signing here:
https://developer.apple.com/library/mac/documentation/Security/Conceptual/CodeSigningGuide/Introduction/Introduction.html

