In Objective-C with ARC, is it true that we usually only need to specify nonatomic as property attributes?

Question

It is strange that in Big Nerd Ranch iOS 5 book (p.73) and Programming iOS 5 book (O\'Reilly, p.314) (updadte: even Kochan\'s Objective-C book Fourth edition)

Answer 1

By default, an object property is strong, atomic, readwrite. See https://developer.apple.com/library/ios/documentation/Cocoa/Conceptual/ProgrammingWithObjectiveC/EncapsulatingData/EncapsulatingData.html