https://qooah.com/2012/11/19/nexus-4%e5%b7%a5%e5%85%b7%e5%8c%85%e5%87%ba%e7%88%90-%e5%8f%af%e4%bb%a5%e8%a7%a3%e9%8e%96%e3%80%81root%e3%80%81%e5%82%99%e4%bb%bd%e7%ad%89%e5%a4%9a%e5%80%8b%e5%8a%9f%e8%83%bd/