I use the following script so scroll to the div "#content-element" on first scroll. On desktop this is working smoothly but on iOs phones this effect is kind of lagging. Is there any idea why this could be?

window.wasScrolled = false;
$(window).bind('scroll',function(){
    if (!window.wasScrolled) { 
        $('html, body').stop().animate({scrollTop:document.getElementById('content-wrapper').getBoundingClientRect().top},1000)                     
    }
    window.wasScrolled = true;
});