安装：

1 final Intent intent = new Intent(Intent.ACTION_VIEW);
2 intent.setDataAndType(Uri.fromFile(new File(Environment.getExternalStorageDirectory(), APK_FILE_NAME)),
3          "application/vnd.android.package-archive");
4 context.startActivity(intent);

卸载：

1 Uri packageURI = Uri.parse("package:com.myapp");
2 Intent uninstallIntent = new Intent(Intent.ACTION_DELETE, packageURI);
3 context.startActivity(uninstallIntent);