diff --git a/HISTORY.md b/HISTORY.md
index 7456d461..bd3424f8 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -16,6 +16,8 @@ http://visjs.org
 
 - Fixed #1001: First element of group style being cut.
 - Fixed #1071: HTML contents of a group not cleared when the contents is updated.
+- Fixed #1033: Moved item data not updated in DataSet when using an asynchronous
+  `onMove` handler.
 
 
 ## 2015-07-03, version 4.4.0
diff --git a/lib/timeline/component/ItemSet.js b/lib/timeline/component/ItemSet.js
index 8509c021..cd763249 100644
--- a/lib/timeline/component/ItemSet.js
+++ b/lib/timeline/component/ItemSet.js
@@ -46,7 +46,7 @@ function ItemSet(body, options) {
       remove: false
     },
 
-    snap:  TimeStep.snap,
+    snap: TimeStep.snap,
 
     onAdd: function (item, callback) {
       callback(item);
@@ -1345,13 +1345,11 @@ ItemSet.prototype._onDragEnd = function (event) {
   if (this.touchParams.itemProps) {
     event.stopPropagation();
 
-    // prepare a change set for the changed items
-    var changes = [];
     var me = this;
     var dataset = this.itemsData.getDataSet();
-
     var itemProps = this.touchParams.itemProps ;
     this.touchParams.itemProps = null;
+
     itemProps.forEach(function (props) {
       var id = props.item.id;
       var exists = me.itemsData.get(id, me.itemOptions) != null;
@@ -1376,7 +1374,7 @@ ItemSet.prototype._onDragEnd = function (event) {
           if (itemData) {
             // apply changes
             itemData[dataset._fieldId] = id; // ensure the item contains its id (can be undefined)
-            changes.push(itemData);
+            dataset.update(itemData);
           }
           else {
             // restore original values
@@ -1388,11 +1386,6 @@ ItemSet.prototype._onDragEnd = function (event) {
         });
       }
     });
-
-    // apply the changes to the data (if there are changes)
-    if (changes.length) {
-      dataset.update(changes);
-    }
   }
 };