diff --git a/calculatorpp/src/main/java/org/solovyev/android/calculator/overlay/CalculatorOverlayService.java b/calculatorpp/src/main/java/org/solovyev/android/calculator/overlay/CalculatorOverlayService.java
index 7a611ca5..bf12d73d 100644
--- a/calculatorpp/src/main/java/org/solovyev/android/calculator/overlay/CalculatorOverlayService.java
+++ b/calculatorpp/src/main/java/org/solovyev/android/calculator/overlay/CalculatorOverlayService.java
@@ -46,6 +46,7 @@ public class CalculatorOverlayService extends Service implements ExternalCalcula
     @Override
     public void onCreate() {
         super.onCreate();
+
 		final WindowManager wm = (WindowManager) getSystemService(WINDOW_SERVICE);
 
 		final LayoutInflater layoutInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
@@ -72,8 +73,8 @@ public class CalculatorOverlayService extends Service implements ExternalCalcula
 
 
 		final WindowManager.LayoutParams params = new WindowManager.LayoutParams(
-				300,
-				450,
+				Math.max(wm.getDefaultDisplay().getWidth() / 2, 300),
+				Math.max(wm.getDefaultDisplay().getHeight() / 2, 450),
 				WindowManager.LayoutParams.TYPE_SYSTEM_ALERT,
 				WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE|WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL|WindowManager.LayoutParams.FLAG_WATCH_OUTSIDE_TOUCH,
 				PixelFormat.TRANSLUCENT);