Html2Canvas image (PNG) not downloading in IOS and Android WebView

Question

I am using html2canvas to convert html to image (PNG file) and trigger download in user's device. I have tested the code, works well in all desktop browser but not working in IOS and android webview. Below is the code I am using:

$('#btnDownload').click(function () {
            $('.section-loading').show();
            html2canvas($('#divDownload'),
                {
                    background: '#fff',
                    onrendered: function (canvas) {
                        if (navigator.userAgent.indexOf("MSIE ") > 0 ||
                            navigator.userAgent.match(/Trident.*rv\:11\./)) {
                            var blob = canvas.msToBlob();
                            window.navigator.msSaveBlob(blob, 'Receipt.png');
                        }
                        else {
                            $('#download').attr('href', canvas.toDataURL("image/png"));
                            $('#download').attr('download', 'Receipt.png');
                            $('#download')[0].click();
                        }

                        $('.section-loading').hide();
                    }
                });
        });