diff --git a/apps/tests/app/binding_tests.ts b/apps/tests/app/binding_tests.ts
index 1ac9cb323..63fafa18a 100644
--- a/apps/tests/app/binding_tests.ts
+++ b/apps/tests/app/binding_tests.ts
@@ -1,24 +1,32 @@
 import pageModule = require("ui/page");
 //import stackLayoutModule = require("ui/layouts/stack-layout");
 //import textFieldModule = require("ui/text-field");
+import buttonModule = require("ui/button");
 import observableModule = require("data/observable");
+import observableArray = require("data/observable-array");
 import bindableModule = require("ui/core/bindable");
 //import enums = require("ui/enums");
 import trace = require("trace");
-trace.setCategories(trace.categories.Test);
+trace.setCategories(trace.categories.Test + "," + trace.categories.Binding);
 trace.enable();
 
 export function pageLoaded(args: observableModule.EventData) {
     var page: pageModule.Page = <pageModule.Page>args.object;
     var model = new observableModule.Observable();
+    var tasks = new observableArray.ObservableArray();
+    //tasks.push("tralala");
     //var model = page.bindingContext;
+    model.set("tasks", tasks);
     model.set("paramProperty", "%%%");
     var toUpperConverter: bindableModule.ValueConverter = {
         toModel: function (value, param1) {
             return param1 + value.toLowerCase();
         },
         toView: function (value, param1) {
-            return value.toUpperCase();
+            if (value === 0) {
+                return "no items";
+            }
+            return value + " items";
         }
     };
     model.set("toUpper", toUpperConverter);
@@ -27,6 +35,12 @@ export function pageLoaded(args: observableModule.EventData) {
     page.bindingContext = model;
 }
 
+export function onTap(args: observableModule.EventData) {
+    var button: buttonModule.Button = <buttonModule.Button>args.object;
+    trace.write("tasks: " + button.bindingContext.get("tasks"), trace.categories.Test, trace.messageType.info);
+    button.bindingContext.get("tasks").push("alabala");
+}
+
 //export function createPage() {
 //    var stackLayout = new stackLayoutModule.StackLayout();
 //    var firstTextField = new textFieldModule.TextField();
diff --git a/apps/tests/app/binding_tests.xml b/apps/tests/app/binding_tests.xml
index 66f6fd7d5..4fa341b83 100644
--- a/apps/tests/app/binding_tests.xml
+++ b/apps/tests/app/binding_tests.xml
@@ -1,7 +1,6 @@
 <Page xmlns="http://www.nativescript.org/tns.xsd" loaded="pageLoaded">
     <StackLayout padding="7">
-        <TextField text="{{ testProperty, testProperty | toUpper(paramProperty) }}" />
-        <!--<TextField text="{{ testProperty | toUpper }}" />-->
-        <TextField text="{{ testProperty }}" />
+        <TextField text="{{ tasks.length, tasks.length === 0 ? 'zero items' : tasks.length + ' items', false }}" />
+        <Button text="Click" tap="onTap" />
     </StackLayout>
 </Page>
\ No newline at end of file
diff --git a/apps/tests/observable-array-tests.ts b/apps/tests/observable-array-tests.ts
index 713f453d4..8d7029546 100644
--- a/apps/tests/observable-array-tests.ts
+++ b/apps/tests/observable-array-tests.ts
@@ -1,4 +1,5 @@
 import TKUnit = require("./TKUnit");
+import bindableModule = require("ui/core/bindable");
 require("globals");
 
 // <snippet module="data/observable-array" title="observable-array">
@@ -80,34 +81,6 @@ export var test_ObservableArray_concatShouldReturnNewArrayWithNewItemsAtTheEnd =
     TKUnit.assert(result.length === 6 && result[4] === 5, "ObservableArray concat() should add items at the end!");
 };
 
-export var test_ObservableArray_concatShouldReturnNewArrayWithNewItemsAtTheEndAndRaiseChangeEventWithCorrectArgs = function () {
-    var result: observableArrayModule.ChangedData<number>;
-    // <snippet module="data/observable-array" title="observable-array">
-    // ### Use concat() method to append array to ObservableArray and handle "change" event.
-    // ``` JavaScript
-    var array = new observableArrayModule.ObservableArray([1, 2, 3]);
-
-    array.on(observableArrayModule.knownEvents.change, (args: observableArrayModule.ChangedData<number>) => {
-        //// Argument (args) is ChangedData<T>.
-        //// args.eventName is "change".
-        //// args.action is "add".
-        //// args.index is equal to the array length.
-        //// args.removed.length is 0.
-        //// args.addedCount is equal to number of added items.
-
-        // <hide>
-        result = args;
-        // </hide>
-    });
-
-    array.concat([4, 5, 6]);
-    // ```
-    // </snippet>
-
-    TKUnit.assert(result.eventName === "change" && result.action === observableArrayModule.ChangeType.Add &&
-        result.removed.length === 0 && result.index === 3 && result.addedCount === 3, "ObservableArray concat() should raise 'change' event with correct args!");
-};
-
 export var test_ObservableArray_joinShouldReturnStringWithAllItemsSeparatedWithComma = function () {
     // <snippet module="data/observable-array" title="observable-array">
     // ### Use join() method to convert ObservableArray to comma separated string.
@@ -135,10 +108,16 @@ export var test_ObservableArray_popShouldRemoveTheLastElement = function () {
     // ### Use pop() method to remove the last element.
     // ``` JavaScript
     var array = new observableArrayModule.ObservableArray([1, 2, 3]);
+    // <hide>
+    var bindable = new bindableModule.Bindable();
+    bindable.set("testProperty", 0);
+    bindable.bind({ sourceProperty: "length", targetProperty: "testProperty" }, array);
+    // </hide>
     var result = array.pop();
     // ```
     // </snippet>
     TKUnit.assert(result === 3 && array.length === 2, "ObservableArray pop() should remove last element!");
+    TKUnit.assert(bindable.get("testProperty") === array.length, "Expected: " + array.length + ", Actual: " + bindable.get("testProperty"));
 };
 
 export var test_ObservableArray_popShouldRemoveTheLastElementAndRaiseChangeEventWithCorrectArgs = function () {
@@ -176,10 +155,16 @@ export var test_ObservableArray_pushShouldAppendNewElement = function () {
     // ### Use push() method to add single element to the array.
     // ``` JavaScript
     var array = new observableArrayModule.ObservableArray([1, 2, 3]);
+    // <hide>
+    var bindable = new bindableModule.Bindable();
+    bindable.set("testProperty", 0);
+    bindable.bind({ sourceProperty: "length", targetProperty: "testProperty" }, array);
+    // </hide>
     var result = array.push(4);
     // ```
     // </snippet>
     TKUnit.assert(result === 4 && array.getItem(3) === 4, "ObservableArray push() should append new element!");
+    TKUnit.assert(bindable.get("testProperty") === array.length, "Expected: " + array.length + ", Actual: " + bindable.get("testProperty"));
 };
 
 export var test_ObservableArray_pushShouldAppendNewElementAndRaiseChangeEventWithCorrectArgs = function () {
@@ -215,10 +200,16 @@ export var test_ObservableArray_pushShouldAppendNewElements = function () {
     // ### Use push() method to add multiple elements to the array.
     // ``` JavaScript
     var array = new observableArrayModule.ObservableArray([1, 2, 3]);
+    // <hide>
+    var bindable = new bindableModule.Bindable();
+    bindable.set("testProperty", 0);
+    bindable.bind({ sourceProperty: "length", targetProperty: "testProperty" }, array);
+    // </hide>
     var result = array.push(4, 5, 6);
     // ```
     // </snippet>
     TKUnit.assert(result === 6 && array.getItem(5) === 6, "ObservableArray push() should append new elements!");
+    TKUnit.assert(bindable.get("testProperty") === array.length, "Expected: " + array.length + ", Actual: " + bindable.get("testProperty"));
 };
 
 export var test_ObservableArray_pushShouldAppendNewElementsAndRaiseChangeEventWithCorrectArgs = function () {
@@ -254,10 +245,16 @@ export var test_ObservableArray_pushShouldAppendNewElementsFromSourceArray = fun
     // ### Use push() method to add multiple elements from source array to the ObservableArray.
     // ``` JavaScript
     var array = new observableArrayModule.ObservableArray([1, 2, 3]);
+    // <hide>
+    var bindable = new bindableModule.Bindable();
+    bindable.set("testProperty", 0);
+    bindable.bind({ sourceProperty: "length", targetProperty: "testProperty" }, array);
+    // </hide>
     var result = array.push([4, 5, 6]);
     // ```
     // </snippet>
     TKUnit.assert(result === 6 && array.getItem(5) === 6, "ObservableArray push() should append new elements from source array!");
+    TKUnit.assert(bindable.get("testProperty") === array.length, "Expected: " + array.length + ", Actual: " + bindable.get("testProperty"));
 };
 
 export var test_ObservableArray_pushShouldAppendNewElementsFromSourceArrayAndRaiseChangeEventWithCorrectArgs = function () {
@@ -304,10 +301,16 @@ export var test_ObservableArray_shiftShouldRemoveTheFirstElement = function () {
     // ### Use shift() method to remove the first element of the array.
     // ``` JavaScript
     var array = new observableArrayModule.ObservableArray([1, 2, 3]);
+    // <hide>
+    var bindable = new bindableModule.Bindable();
+    bindable.set("testProperty", 0);
+    bindable.bind({ sourceProperty: "length", targetProperty: "testProperty" }, array);
+    // </hide>
     var result = array.shift();
     // ```
     // </snippet>
     TKUnit.assert(result === 1 && array.length === 2, "ObservableArray shift() should remove first element!");
+    TKUnit.assert(bindable.get("testProperty") === array.length, "Expected: " + array.length + ", Actual: " + bindable.get("testProperty"));
 };
 
 export var test_ObservableArray_shiftShouldRemoveTheFirstElementAndRaiseChangeEventWithCorrectArgs = function () {
@@ -388,11 +391,17 @@ export var test_ObservableArray_spliceShouldRemoveSpecifiedNumberOfElementsStart
     // ### Use splice(start, deleteCount) method to delete elements in the array. 
     // ``` JavaScript
     var array = new observableArrayModule.ObservableArray(["one", "two", "three"]);
+    // <hide>
+    var bindable = new bindableModule.Bindable();
+    bindable.set("testProperty", 0);
+    bindable.bind({ sourceProperty: "length", targetProperty: "testProperty" }, array);
+    // </hide>
     var result = array.splice(1, 2);
     // ```
     // </snippet>
     TKUnit.assert(result.length === 2 && result[0] === "two" && array.length === 1 && array.getItem(0) === "one",
         "ObservableArray splice() should remove specified number of elements starting from specified index!");
+    TKUnit.assert(bindable.get("testProperty") === array.length, "Expected: " + array.length + ", Actual: " + bindable.get("testProperty"));
 };
 
 export var test_ObservableArray_spliceShouldRemoveSpecifiedNumberOfElementsStartingFromSpecifiedIndexAndRaiseChangeEventWithCorrectArgs = function () {
@@ -470,11 +479,17 @@ export var test_ObservableArray_unshiftShouldInsertNewElementsFromTheStart = fun
     // ### Use unshift(item1, item2... itemN) method to insert elements from the start of the array.
     // ``` JavaScript
     var array = new observableArrayModule.ObservableArray([1, 2, 3]);
+    // <hide>
+    var bindable = new bindableModule.Bindable();
+    bindable.set("testProperty", 0);
+    bindable.bind({ sourceProperty: "length", targetProperty: "testProperty" }, array);
+    // </hide>
     var result = array.unshift(4, 5);
     // ```
     // </snippet>
 
     TKUnit.assert(array.getItem(0) === 4 && result === 5 && array.length === 5, "ObservableArray unshift() should insert new elements from the start!");
+    TKUnit.assert(bindable.get("testProperty") === array.length, "Expected: " + array.length + ", Actual: " + bindable.get("testProperty"));
 };
 
 export var test_ObservableArray_unshiftShouldInsertNewElementsFromTheStartAndRaiseChangeEventWithCorrectArgs = function () {
diff --git a/apps/tests/ui/bindable-tests.ts b/apps/tests/ui/bindable-tests.ts
index 1245e13ee..8cc886578 100644
--- a/apps/tests/ui/bindable-tests.ts
+++ b/apps/tests/ui/bindable-tests.ts
@@ -380,3 +380,43 @@ export var test_Bindable_BindingContext_String_DoesNotThrow = function () {
 
     TKUnit.assert(obj.get("test") === 6, "Expected: 6; Actual: " + obj.get("test"));
 }
+
+export var test_getBindableOptionsFromStringFullFormat = function () {
+    var bindingExpression = "bindProperty, bindProperty * 2, false";
+    var bindOptions = bindable.Bindable._getBindingOptions("targetBindProperty", bindingExpression);
+
+    TKUnit.assert(bindOptions.sourceProperty === "bindProperty", "Expected: bindProperty, Actual: " + bindOptions.sourceProperty);
+    TKUnit.assert(bindOptions.targetProperty === "targetBindProperty", "Expected: targetBindProperty, Actual: " + bindOptions.targetProperty);
+    TKUnit.assert(bindOptions.expression === "bindProperty * 2", "Expected: bindProperty * 2, Actual:" + bindOptions.expression);
+    TKUnit.assert(bindOptions.twoWay === false, "Expected: false, Actual: " + bindOptions.twoWay);
+}
+
+export var test_getBindableOptionsFromStringShortFormatExpression = function () {
+    var bindingExpression = "bindProperty * 2";
+    var bindOptions = bindable.Bindable._getBindingOptions("targetBindProperty", bindingExpression);
+
+    TKUnit.assert(bindOptions.sourceProperty === "bindProperty", "Expected: bindProperty, Actual: " + bindOptions.sourceProperty);
+    TKUnit.assert(bindOptions.targetProperty === "targetBindProperty", "Expected: targetBindProperty, Actual: " + bindOptions.targetProperty);
+    TKUnit.assert(bindOptions.expression === "bindProperty * 2", "Expected: bindProperty * 2, Actual: " + bindOptions.expression);
+    TKUnit.assert(bindOptions.twoWay === true, "Expected: true, Actual: " + bindOptions.twoWay);
+}
+
+export var test_getBindableOptionsFromStringShortFormatProperty = function () {
+    var bindingExpression = "bindProperty";
+    var bindOptions = bindable.Bindable._getBindingOptions("targetBindProperty", bindingExpression);
+
+    TKUnit.assert(bindOptions.sourceProperty === "bindProperty", "Expected: bindProperty, Actual: " + bindOptions.sourceProperty);
+    TKUnit.assert(bindOptions.targetProperty === "targetBindProperty", "Expected: targetBindProperty, Actual: " + bindOptions.targetProperty);
+    TKUnit.assert(bindOptions.expression === null, "Expected: null, Actual: " + bindOptions.expression);
+    TKUnit.assert(bindOptions.twoWay === true, "Expected: true, Actual: " + bindOptions.twoWay);
+}
+
+export var test_getBindableOptionsFromStringTwoParamsFormat = function () {
+    var bindingExpression = "bindProperty, bindProperty * 2";
+    var bindOptions = bindable.Bindable._getBindingOptions("targetBindProperty", bindingExpression);
+
+    TKUnit.assert(bindOptions.sourceProperty === "bindProperty", "Expected: bindProperty, Actual: " + bindOptions.sourceProperty);
+    TKUnit.assert(bindOptions.targetProperty === "targetBindProperty", "Expected: targetBindProperty, Actual: " + bindOptions.targetProperty);
+    TKUnit.assert(bindOptions.expression === "bindProperty * 2", "Expected: bindProperty * 2, Actual:" + bindOptions.expression);
+    TKUnit.assert(bindOptions.twoWay === true, "Expected: true, Actual: " + bindOptions.twoWay);
+}
\ No newline at end of file
diff --git a/data/observable-array/observable-array.ts b/data/observable-array/observable-array.ts
index 62f37e209..1bed9ea06 100644
--- a/data/observable-array/observable-array.ts
+++ b/data/observable-array/observable-array.ts
@@ -88,13 +88,7 @@ export class ObservableArray<T> extends observable.Observable implements observa
      */
     concat(): T[] {
         this._addArgs.index = this._array.length;
-
         var result = this._array.concat.apply(this._array, arguments);
-
-        this._addArgs.addedCount = result.length - this._array.length;
-
-        this.notify(this._addArgs);
-
         return result;
     }
 
@@ -117,6 +111,7 @@ export class ObservableArray<T> extends observable.Observable implements observa
         this._deleteArgs.removed = [result];
 
         this.notify(this._deleteArgs);
+        this._notifyLengthChange();
 
         return result;
     }
@@ -143,10 +138,16 @@ export class ObservableArray<T> extends observable.Observable implements observa
         this._addArgs.addedCount = this._array.length - this._addArgs.index;
 
         this.notify(this._addArgs);
+        this._notifyLengthChange();
 
         return this._array.length;
     }
 
+    _notifyLengthChange() {
+        var lengthChangedData = this._createPropertyChangeData("length", this._array.length);
+        this.notify(lengthChangedData);
+    }
+
     /**
      * Reverses the elements in an Array. 
      */
@@ -164,6 +165,7 @@ export class ObservableArray<T> extends observable.Observable implements observa
         this._deleteArgs.removed = [result];
 
         this.notify(this._deleteArgs);
+        this._notifyLengthChange();
 
         return result;
     }
@@ -202,6 +204,9 @@ export class ObservableArray<T> extends observable.Observable implements observa
             removed: result,
             addedCount: this._array.length > length ? this._array.length - length : 0
         });
+        if (this._array.length !== length) {
+            this._notifyLengthChange();
+        }
 
         return result;
     }
@@ -218,6 +223,7 @@ export class ObservableArray<T> extends observable.Observable implements observa
         this._addArgs.addedCount = result - length;
 
         this.notify(this._addArgs);
+        this._notifyLengthChange();
 
         return result;
     }
diff --git a/ui/builder/component-builder.ts b/ui/builder/component-builder.ts
index e50199b9f..e0c86e84a 100644
--- a/ui/builder/component-builder.ts
+++ b/ui/builder/component-builder.ts
@@ -114,7 +114,7 @@ export function getComponentModule(elementName: string, namespace: string, attri
                 gridLayoutModule.GridLayout.setColumnSpan(instance, !isNaN(+attrValue) && +attrValue);
             } else if (attr === ROW_SPAN) {
                 gridLayoutModule.GridLayout.setRowSpan(instance, !isNaN(+attrValue) && +attrValue);
-            } if (attr === LEFT) {
+            } else if (attr === LEFT) {
                 absoluteLayoutDef.AbsoluteLayout.setLeft(instance, !isNaN(+attrValue) && +attrValue);
             } else if (attr === TOP) {
                 absoluteLayoutDef.AbsoluteLayout.setTop(instance, !isNaN(+attrValue) && +attrValue);
diff --git a/ui/core/bindable.ts b/ui/core/bindable.ts
index 755c0b602..5e213be20 100644
--- a/ui/core/bindable.ts
+++ b/ui/core/bindable.ts
@@ -120,7 +120,7 @@ export class Bindable extends dependencyObservable.DependencyObservable implemen
     private static extractPropertyNameFromExpression(expression: string): string {
         var firstExpressionSymbolIndex = expression.search(expressionSymbolsRegex);
         if (firstExpressionSymbolIndex > -1) {
-            return expression.substr(0, firstExpressionSymbolIndex);
+            return expression.substr(0, firstExpressionSymbolIndex).trim();
         }
         else {
             return expression;
@@ -135,9 +135,16 @@ export class Bindable extends dependencyObservable.DependencyObservable implemen
         };
         if (types.isString(bindingExpression)) {
             var params = bindingExpression.split(",");
-            result.sourceProperty = Bindable.extractPropertyNameFromExpression(params[0]);
-            result.expression = params[1];
-            result.twoWay = params[2] ? params[2].toLowerCase() === "true" : true;
+            if (params.length === 1) {
+                result.sourceProperty = Bindable.extractPropertyNameFromExpression(params[0].trim());
+                result.expression = params[0].search(expressionSymbolsRegex) > -1 ? params[0].trim() : null;
+                result.twoWay = true;
+            }
+            else {
+                result.sourceProperty = Bindable.extractPropertyNameFromExpression(params[0].trim());
+                result.expression = params[1].trim();
+                result.twoWay = params[2] ? params[2].toLowerCase().trim() === "true" : true;
+            }
         }
         return result;
     }
@@ -276,7 +283,6 @@ export class Binding {
             this.sourceOptions.property in sourceOptionsInstance) {
             value = sourceOptionsInstance[this.sourceOptions.property];
         }
-
         return value;
     }