"std::ios_base::Init::~Init()", referenced from:

Undefined symbols for architecture armv6:"std::ios_base::Init::~Init()", referenced from:  ___tcf_0 in libmyCppLib_dev.a(myCppLib.o)"std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)", referenced from:      _show_the_world in libmyCppLib_dev.a(myCppLib.o)"std::ios_base::Init::Init()", referenced from:  __static_initialization_and_destruction_0(int,int)in libmyCppLib_dev.a(myCppLib.o)"std::cout", referenced from:  _show_the_world in libmyCppLib_dev.a(myCppLib.o)ld: symbol(s) not found for architecture armv6collect2: ld returned 1 exit status

The correct answer was provided by Jimmy Koerting in the comments: the app needs to be linked against libstdc++.dylib to resolve the standard library symbols. Thanks to Jimmy Koerting, but one more thing i want to add here is, if you are using xcode latest version with iOS 6.1 please add thislibstdc++.6.dylib

http://stackoverflow.com/questions/6882817/building-static-c-lib-for-use-with-objective-c-app-in-xcode-4