https://blog.wongcw.com/2018/09/19/ios-12-1%e6%96%b0%e5%8f%91%e7%8e%b0%ef%bc%9amemoji%e5%b0%86%e6%94%af%e6%8c%81icloud%e5%90%8c%e6%ad%a5/