https://blog.wongcw.com/2020/07/01/%e6%9c%aa%e4%be%86iphone%e4%b9%8b%e9%96%93%e7%9a%84airdrop%e5%8f%af%e8%83%bd%e4%bd%bf%e7%94%a8%e6%bf%80%e5%85%89%e5%bf%ab%e9%80%9f%e5%82%b3%e8%bc%b8%e5%a4%a7%e6%96%87%e4%bb%b6/