$(function(){

var $toggleImg = $('.toggleImg');

    function fnToggleImg(e){
        if (e.type == 'click') {
            $(this).data('clicked', !$(this).data('clicked'));
        } else if (!$(this).data('clicked')) {
            this.src = this.src.indexOf('-hover') == -1 ? this.src.replace("-normal", "-hover") : this.src.replace("-hover", "-normal");
        }
    }

    if (Modernizr.touch){
        $toggleImg.hammer();

            $('img.rollover').on('touchstart touchend', fnToggleImg);
         } else {
            $('img.rollover').on('mouseenter mouseleave', fnToggleImg);
    }

$toggleImg.on(Modernizr.touch ? 'tap' : 'click', fnToggleImg);

});