https://purengom.com/2010/06/20/iphone%ec%95%84%ec%9d%b4%ed%8f%b0-%ec%a0%84%ed%99%94-%ed%8e%b8%ec%9d%98-%ea%b8%b0%eb%8a%a5-%ec%82%ac%ec%9a%a9-%ed%95%98%ea%b8%b0/