Is there a way to remove the clicking lag on mobile touch devices?

Question

When viewing a web site on a mobile device (iPad, Galaxy Tab) there's always a lag when I click an element (regular link or anything else that is made clickable using javascript/jquery).

While reading online, I found out that the browser is using touchstart followed by touchend events, and afterwards it triggers the regular click event. Is there a way to have a more responsive tap and remove the click event that is delayed? Maybe by using javascript, or something else?

Answer 1

Adapted from Matt's library (https://stackoverflow.com/a/9370637/1491212) itself adapted from google code, I wrote a jQuery plugin.

Use like this : $('mySelector').fastClick(handler);

(function($){
    var clickbuster = {
        preventGhostClick: function(x, y) {
          clickbuster.coordinates.push(x, y);
          window.setTimeout(clickbuster.pop, 2500);
        },
        pop: function() {
          clickbuster.coordinates.splice(0, 2);
        },
        onClick: function(event) {
          for (var i = 0; i < clickbuster.coordinates.length; i += 2) {
            var x = clickbuster.coordinates[i];
            var y = clickbuster.coordinates[i + 1];
            if (Math.abs(event.clientX - x) < 25 && Math.abs(event.clientY - y) < 25) {
              event.stopPropagation();
              event.preventDefault();
            }
          }
        }
    };


    var methods = {
        init: function(handler){
            return this.each(function() {
                var $this = $(this),
                    data = $this.data('fastClick');
                if(!data){
                    this.addEventListener('touchstart', methods.handleEvent, false);
                    this.addEventListener('click', methods.handleEvent, false);
                    $this.data('fastClick', {
                        target: $this,
                        handler: handler
                    });
                }
            });
        },
        handleEvent:function(event) {
          switch (event.type) {
            case 'touchstart': $(this).fastClick('onTouchStart',event); break;
            case 'touchmove': $(this).fastClick('onTouchMove',event); break;
            case 'touchend': $(this).fastClick('onClick',event); break;
            case 'click': $(this).fastClick('onClick',event); break;
          }
        },
        onTouchStart: function(event) {
          event.stopPropagation();
          this[0].addEventListener('touchend', methods.handleEvent, false);
          var _this = this;
          document.body.addEventListener('touchmove', function(event){
            methods.handleEvent.apply(_this,[event]);
          }, false);

          $(this).data('fastClick').startX = event.touches[0].clientX;
          $(this).data('fastClick').startY = event.touches[0].clientY;
        },
        onTouchMove: function(event) {
          if (Math.abs(event.touches[0].clientX - this.data('fastClick').startX) > 10 ||
              Math.abs(event.touches[0].clientY - this.data('fastClick').startY) > 10) {
              this.fastClick('reset');
          }
        },
        onClick: function(event) {
          event.stopPropagation();
          $(this).fastClick('reset');
          $(this).data('fastClick').handler.call(this,event);

          if (event.type == 'touchend') {
            clickbuster.preventGhostClick($(this).data('fastClick').startX, $(this).data('fastClick').startY);
          }
        },
        reset: function() {
          this[0].removeEventListener('touchend', methods.handleEvent, false);
          document.body.removeEventListener('touchmove', methods.handleEvent, false);
        }
    }
    $.fn.fastClick = function(method) {
        if (methods[method]) {
            return methods[method].apply(this, Array.prototype.slice.call(arguments, 1));
        } else if ( typeof method === 'object' || typeof method === 'function' || !method) {
            return methods.init.apply(this, arguments);
        } else {
            $.error('Method ' + method + ' does not exist on jQuery.hScroll');
        }

    }

    clickbuster.coordinates = [];
    document.addEventListener('click', clickbuster.onClick, true);

})(jQuery);

Answer 2

if you are writing a web page your self you can register a listener for touchstart and touchend and trigger the onclick code directly from on touch end without any delay.

If you don`t handle the event in touch move the browser will dispatch (with some lag) a click event to the element

Take a look at this description from google to create "fast buttons": http://code.google.com/intl/de-DE/mobile/articles/fast_buttons.html