https://qooah.com/2011/08/31/%e9%bb%91%e5%ae%a2%e8%a9%a6%e5%9c%96%e5%9c%a8-android-%e4%b8%8a%e6%a8%a1%e6%93%ac%e9%81%8b%e8%a1%8c-ios-apps/