https://blog.wongcw.com/2018/10/05/ios-12-%e6%99%ae%e5%8f%8a%e7%8e%87%e5%b7%b2%e8%be%be-46-%e5%8d%b3%e5%b0%86%e8%b6%85%e8%bf%87-ios-11-2/
iOS 12 普及率已达 46% 即将超过 iOS 11