I understand that those who installed Xcode 4 via the developer site are able to uninstall via /Developer/Library/uninstall-devtools –mode=all
, however I installed
If you have installed xcode from Mac App store, then you need to delete it from Launch pad. You can do this by locating xcode icon in launch pad, long click on the icon till it starts dancing. Then delete it and wait for a while till the xcode.app is deleted from /Application. If you manually delete xcode.app from /Application, App store will continue to think its installed and will not allow you to reinstall in future.