as you mention you have follow these steps already please set compiler flags for JSONkit.m file also -fno-objc-arc
also
if its not working then tried:-
1.you can delete the App directy under ~/Library/Application Support/iPhone Simulator/6.0/Applications and ~/Library/Developer/Xcode/DerivedData
2.then you can start Xcode ; in the menubar you can find Project -> Clean!