Not working on iPad 1 about easy-pie-chart HOT 1 CLOSED

jQuery(document).ready(function() {
    $('.chart').easyPieChart({
        size: '200',
        lineWidth: '6',
        lineCap: 'square',
        scaleColor: '#d5d5d5',
        trackColor: '#eeeeee',
        barColor: '#0099cc',
        easing: 'easeOutBounce',
        onStep: function(from, to, percent) {
            $(this.el).find('.percent').text(Math.round(percent));
        }
    });

    var chart = window.chart = $('.chart').data('easyPieChart');

    $('.js_update').on('click', function() {
        chart.update(Math.random()*100);
    });
});