It seems that the directory for the iOS Simulator has changed. It used to be in ~/Library/Application\\ Support/iPhone\\ Simulator/ and now it\'s in ~/Lib
~/Library/Application\\ Support/iPhone\\ Simulator/
~/Lib
Update for iOS 9: You have to disable App Transport Security to use Charles!
http://www.charlesproxy.com/documentation/using-charles/ssl-certificates/