In some cases, you want to disable ARC in your project just for one or some subset of files. Usually this is the case, for me, that I’m using a file from an online repository that I don’t want to change for various reasons. The way to disable ARC for that file is in the Read more about Disable ARC Compilation in Xcode for an iOS/Objective-C File[…]
you have to select the device in the schemes menu in the top left where you used to select between simulator/device. it won’t let you archive a build for simulator. via xcode4 – Xcode 4 – “Archive” is greyed out? – Stack Overflow.