https://cocoapods.org/   뭐가 이렇게 많은지..  몇일전에 봤던 글이 생각나네요..

http://sir.kr/cm_free/1372424 

http://stackoverflow.com/questions/20755044/how-to-install-cocoa-pods 

react-native link명령에 이것이 필요하다고 하네요.

sudo gem install activesupport -v 4.2.6

sudo gem install -n /usr/local/bin cocoapods

pod setup --verbose