//https://developer.android.com/about/dashboards/index.html#Screens
private static String getDensityName(DisplayMetrics dm) {
        float density = dm.density;
        if (density >= 4.0) {
            return "xxxhigh density";
        }
        if (density >= 3.0) {
            return "xxhigh density";
        }
        if (density >= 2.0) {
            return "xhigh density";
        }
        if (density >= 1.5) {
            return "high density";
        }
        if (density >= 1.0) {
            return "medium density";
        }
        return "low density";
    }