diff --git a/README.md b/README.md
index 06ad48048..59104d4d5 100755
--- a/README.md
+++ b/README.md
@@ -89,7 +89,7 @@ List of Definitions
 * [iCheck](http://damirfoy.com/iCheck/) (by [Dániel Tar](https://github.com/qcz))
 * [Impress.js](https://github.com/bartaz/impress.js) (by [Boris Yankov](https://github.com/borisyankov))
 * [Intl](http://www.ecma-international.org/ecma-402/1.0/) (by [Jeffery Grajkowski](http://github.com/pushplay))
-* [iScroll](http://cubiq.org/iscroll-4) (by [Boris Yankov](https://github.com/borisyankov))
+* [iScroll](http://cubiq.org/iscroll-4) (by [Boris Yankov](https://github.com/borisyankov) and [Christiaan Rakowski](https://github.com/csrakowski))
 * [jake](https://github.com/mde/jake) (by [Kon](http://phyzkit.net/))
 * [Jasmine](http://pivotal.github.com/jasmine/) (by [Boris Yankov](https://github.com/borisyankov))
 * [Jasmine-jQuery](https://github.com/velesin/jasmine-jquery) (by [Gregor Stamac](https://github.com/gstamac))
diff --git a/iscroll/iscroll-lite.d.ts b/iscroll/iscroll-lite.d.ts
index 085f844b0..1cd83b1dd 100644
--- a/iscroll/iscroll-lite.d.ts
+++ b/iscroll/iscroll-lite.d.ts
@@ -1,6 +1,6 @@
 // Type definitions for iScroll Lite 4.1
 // Project: http://cubiq.org/iscroll-4
-// Definitions by: Boris Yankov <https://github.com/borisyankov/>
+// Definitions by: Boris Yankov <https://github.com/borisyankov/> and Christiaan Rakowski <https://github.com/csrakowski/>
 // Definitions: https://github.com/borisyankov/DefinitelyTyped
 
 
@@ -39,8 +39,9 @@ declare class iScroll {
 
     destroy(): void;
     refresh(): void;
-    scrollTo(x: number, y: number, time: number, relative: boolean): void;
-    scrollToElement(element: string, time: number): void;
+    scrollTo(x: number, y: number, time?: number, relative?: boolean): void;
+    scrollToElement(element: string, time?: number): void;
+    scrollToElement(element: HTMLElement, time?: number): void;
     disable(): void;
     enable(): void;
     stop(): void;
diff --git a/iscroll/iscroll-tests.ts b/iscroll/iscroll-tests.ts
index e8141d5ea..773b62acf 100644
--- a/iscroll/iscroll-tests.ts
+++ b/iscroll/iscroll-tests.ts
@@ -17,7 +17,15 @@ var myScroll4 = new iScroll('wrapper', {
 var myScroll6 = new iScroll('wrapper', { scrollbarClass: 'myScrollbar' });
 
 myScroll1.refresh();
+myScroll1.scrollTo(0, 100);
+myScroll1.scrollTo(0, 100, 200);
+myScroll1.scrollTo(0, 100, 200, true);
 
+myScroll1.scrollToElement('selectedElement');
+myScroll1.scrollToElement('selectedElement', 250);
+
+myScroll1.scrollToElement(document.getElementById('selectedElement'));
+myScroll1.scrollToElement(document.getElementById('selectedElement'), 250);
 
 var myScroll7 = new iScroll(document.getElementById('wrapper'));
 var myScroll8 = new iScroll(document.getElementById('wrapper'), { scrollbarClass: 'myScrollbar' });
\ No newline at end of file
diff --git a/iscroll/iscroll.d.ts b/iscroll/iscroll.d.ts
index 4c89038ed..34234c00a 100644
--- a/iscroll/iscroll.d.ts
+++ b/iscroll/iscroll.d.ts
@@ -1,6 +1,6 @@
 // Type definitions for iScroll 4.2
 // Project: http://cubiq.org/iscroll-4
-// Definitions by: Boris Yankov <https://github.com/borisyankov/>
+// Definitions by: Boris Yankov <https://github.com/borisyankov/> and Christiaan Rakowski <https://github.com/csrakowski/>
 // Definitions: https://github.com/borisyankov/DefinitelyTyped
 
 
@@ -64,12 +64,13 @@ declare class iScroll {
 
     destroy(): void;
     refresh(): void;
-    scrollTo(x: number, y: number, time: number, relative: boolean): void;
-    scrollToElement(element: string, time: number): void;
-    scrollToPage(pageX: number, pageY: number, time: number): void;
+    scrollTo(x: number, y: number, time?: number, relative?: boolean): void;
+    scrollToElement(element: string, time?: number): void;
+    scrollToElement(element: HTMLElement, time?: number): void;
+    scrollToPage(pageX: number, pageY: number, time?: number): void;
     disable(): void;
     enable(): void;
     stop(): void;
-    zoom(x: number, y: number, scale: number, time: number): void;
+    zoom(x: number, y: number, scale: number, time?: number): void;
     isReady(): boolean;
 }