Viewport setting on Android

screen-viewport.js

//<meta name="viewport" content="width=device-width,height=device-height,user-scalable=yes,target-densitydpi=220,initial-scale=1.0, minimum-scale=1.0, maximum-scale=2.0" /> 
    var viewportContent = '';
    if ((window.devicePixelRatio <= 1 && window.outerWidth > 1024) {
        console.log(" Special Case -> big screen but device pixel ratio is 1 window.outerWidth  : " + window.outerWidth  + " window.outerHeight " + window.outerHeight);
        viewportContent = 'width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=yes, target-densityDpi=device-dpi';
    } else if ((window.devicePixelRatio <= 1) {
         console.log(" RATIO == 1");
        viewportContent = 'width=device-width,height=device-height, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=yes, target-densityDpi=220';
    } else if ((window.devicePixelRatio <= 1.3) {
         console.log(" RATIO == 1.3");
        viewportContent = 'width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=yes, target-densityDpi=medium-dpi';
    } else if (window.devicePixelRatio <= 1.5) {
        console.log(" RATIO == 1.5");
        viewportContent = 'width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=yes, target-densityDpi=high-dpi';
    } else if (window.devicePixelRatio <= 2) {
        console.log(" RATIO == 2");
        viewportContent = 'width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=yes, target-densityDpi=220';
    }else if (window.devicePixelRatio <= 3) {
        console.log(" RATIO == 3");
        viewportContent = 'width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=yes, target-densityDpi=320';
    }else  {
        console.log(" RATIO == " + window.devicePixelRatio);
        viewportContent = 'width=device-width,height=device-height, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=yes, target-densityDpi=device-dpi';
    }
    $('head').append('<meta name="viewport" content="' + viewportContent + '">');
    </script>
/*
console.log("window.devicePixelRatio" + window.devicePixelRatio);
    
    var screenCssPixelRatio = (window.outerWidth - 8) / window.innerWidth;
if (screenCssPixelRatio >= .46 && screenCssPixelRatio <= .54) {
  zoomLevel = "-4";
} else if (screenCssPixelRatio <= .64) {
  zoomLevel = "-3";
} else if (screenCssPixelRatio <= .76) {
  zoomLevel = "-2";
} else if (screenCssPixelRatio <= .92) {
  zoomLevel = "-1";
} else if (screenCssPixelRatio <= 1.10) {
  zoomLevel = "0";
} else if (screenCssPixelRatio <= 1.32) {
  zoomLevel = "1";
} else if (screenCssPixelRatio <= 1.58) {
  zoomLevel = "2";
} else if (screenCssPixelRatio <= 1.90) {
  zoomLevel = "3";
} else if (screenCssPixelRatio <= 2.28) {
  zoomLevel = "4";
} else if (screenCssPixelRatio <= 2.70) {
  zoomLevel = "5";
} else {
  zoomLevel = "unknown";
}

console.log("screenCssPixelRatio : " + screenCssPixelRatio );
    
    
    //<meta name="viewport" content="width=device-width,height=device-height,user-scalable=yes,target-densitydpi=220,initial-scale=1.0, minimum-scale=1.0, maximum-scale=2.0" /> 
    var viewportContent = '';
    if (screenCssPixelRatio <= 1.2) {
    console.log("window.devicePixelRatio 1->" + window.devicePixelRatio + " " + screenCssPixelRatio);
        viewportContent = 'width=device-width,height=device-height, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=yes, target-densityDpi=device-dpi';
    } else if (screenCssPixelRatio <= 1.66) {
    console.log("window.devicePixelRatio 2 -> " + window.devicePixelRatio + " " + screenCssPixelRatio);
        viewportContent = 'width=device-width,height=device-height, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=yes, target-densityDpi=high-dpi';
    }  else if (window.devicePixelRatio <= 2.2) {
    console.log("window.devicePixelRatio 2.2 -> " + window.devicePixelRatio + " " + screenCssPixelRatio);
        viewportContent = 'width=device-width,height=device-height, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=yes, target-densityDpi=220';
    }else  {
    console.log("window.devicePixelRatio other " + window.devicePixelRatio + " " + screenCssPixelRatio);
        viewportContent = 'width=device-width,height=device-height, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=yes, target-densityDpi=device-dpi';
    }
    $('head').append('<meta name="viewport" content="' + viewportContent + '">');
    </script>
    
    */