Should an NSString property under ARC be strong or copy?

Question

When not compiling with ARC, it is recommended to use copy properties for data types such as NSString. I could not find proper documentation on the use of copy in ARC mode. Can someone tell me what's applicable for ARC?

Answer 1

It is still recommended to copy because you want to avoid something passing a mutable string and then changing it without you knowing. A copy guarantees that the string you have will not change.