diff --git a/timer/timer.android.ts b/timer/timer.android.ts
index 8c8ad66ce..2cf7f1c05 100644
--- a/timer/timer.android.ts
+++ b/timer/timer.android.ts
@@ -12,7 +12,11 @@ function createHadlerAndGetId() : number {
     return new Date().getUTCMilliseconds();
 }
 
-export function setTimeout(callback: Function, milliseconds: number): number {
+export function setTimeout(callback: Function, milliseconds?: number): number {
+    if (typeof (milliseconds) !== "number") {
+        milliseconds = 0;
+    }
+
     var id = createHadlerAndGetId();
 
     var runnable = new java.lang.Runnable({
@@ -38,7 +42,11 @@ export function clearTimeout(id: number): void {
     }
 }
 
-export function setInterval(callback: Function, milliseconds: number): number {
+export function setInterval(callback: Function, milliseconds?: number): number {
+    if (typeof (milliseconds) !== "number") {
+        milliseconds = 0;
+    }
+
     var id = createHadlerAndGetId();
 
     var runnable = new java.lang.Runnable({
diff --git a/timer/timer.d.ts b/timer/timer.d.ts
index c5500fbb1..89391242a 100644
--- a/timer/timer.d.ts
+++ b/timer/timer.d.ts
@@ -1,7 +1,7 @@
 /**
   * Timer functions.
   */
-export declare function setTimeout(callback: Function, milliseconds: number): number;
+export declare function setTimeout(callback: Function, milliseconds?: number): number;
 export declare function clearTimeout(id: number): void;
-export declare function setInterval(callback: Function, milliseconds: number): number;
+export declare function setInterval(callback: Function, milliseconds?: number): number;
 export declare function clearInterval(id: number): void;
\ No newline at end of file
diff --git a/timer/timer.ios.ts b/timer/timer.ios.ts
index 8e1167ae4..7f3e814d7 100644
--- a/timer/timer.ios.ts
+++ b/timer/timer.ios.ts
@@ -16,7 +16,11 @@ function createTimerAndGetId(callback: Function, milliseconds: number, shouldRep
     return id;
 }
 
-export function setTimeout(callback: Function, milliseconds: number): number {
+export function setTimeout(callback: Function, milliseconds?: number): number {
+    if (typeof(milliseconds) !== "number") {
+        milliseconds = 0;
+    }
+
     return createTimerAndGetId(callback, milliseconds, false);
 }
 
@@ -28,5 +32,9 @@ export function clearTimeout(id: number): void {
 }
 
 export function setInterval(callback: Function, milliseconds: number): number {
+    if (typeof (milliseconds) !== "number") {
+        milliseconds = 0;
+    }
+
     return createTimerAndGetId(callback, milliseconds, true);
 }