https://qooah.com/2014/05/20/%e6%96%b0%e7%89%88-android-%e5%b0%87%e9%a0%90%e8%a8%ad-art-%e4%ba%a6%e4%bb%a4-root-apps-%e4%b8%8d%e8%83%bd%e9%81%8b%e4%bd%9c/