https://blog.wongcw.com/2018/10/07/ios-12%e5%8d%87%e7%ba%a7%e7%83%ad%e6%83%85%e9%ab%98%e6%b6%a8%ef%bc%9a%e4%b8%8d%e8%b6%b320%e5%a4%a9%e5%ae%89%e8%a3%85%e7%8e%87%e5%b7%b2%e8%bf%87%e5%8d%8a/
iOS 12升级热情高涨:不足20天安装率已过半