Should be doable. When the user has chosen their new icon, just change the value for the "Icon file" in the Info.plist to reference the new image.Thanks for your help but I'm not sure I explained it very well- I want to include in my app I am making the ability to choose from a selection of icon images. If you knew that and I'm just being stupid I'm sorry.
Won't changing the info.plist at runtime break the code signing?