diff --git a/AKPickerView/AKPickerView.swift b/AKPickerView/AKPickerView.swift
index c8370c2..61145a0 100644
--- a/AKPickerView/AKPickerView.swift
+++ b/AKPickerView/AKPickerView.swift
@@ -138,7 +138,7 @@ private class AKCollectionViewLayout: UICollectionViewFlowLayout {
 		let visibleRect = CGRect(origin: self.collectionView!.contentOffset, size: self.collectionView!.bounds.size)
 		self.midX = visibleRect.midX;
 		self.width = visibleRect.width / 2;
-		self.maxAngle = CGFloat(M_PI_2);
+		self.maxAngle = CGFloat(Double.pi/2);
 	}
 
 	fileprivate override func shouldInvalidateLayout(forBoundsChange newBounds: CGRect) -> Bool {
@@ -152,7 +152,7 @@ private class AKCollectionViewLayout: UICollectionViewFlowLayout {
 				return attributes
 			case .wheel:
 				let distance = attributes.frame.midX - self.midX;
-				let currentAngle = self.maxAngle * distance / self.width / CGFloat(M_PI_2);
+				let currentAngle = self.maxAngle * distance / self.width / CGFloat(Double.pi/2);
 				var transform = CATransform3DIdentity;
 				transform = CATransform3DTranslate(transform, -distance, 0, -self.width);
 				transform = CATransform3DRotate(transform, currentAngle, 0, 1, 0);
diff --git a/AKPickerViewSample/Images.xcassets/AppIcon.appiconset/Contents.json b/AKPickerViewSample/Images.xcassets/AppIcon.appiconset/Contents.json
index 36d2c80..1d060ed 100644
--- a/AKPickerViewSample/Images.xcassets/AppIcon.appiconset/Contents.json
+++ b/AKPickerViewSample/Images.xcassets/AppIcon.appiconset/Contents.json
@@ -1,5 +1,15 @@
 {
   "images" : [
+    {
+      "idiom" : "iphone",
+      "size" : "20x20",
+      "scale" : "2x"
+    },
+    {
+      "idiom" : "iphone",
+      "size" : "20x20",
+      "scale" : "3x"
+    },
     {
       "idiom" : "iphone",
       "size" : "29x29",
@@ -30,6 +40,16 @@
       "size" : "60x60",
       "scale" : "3x"
     },
+    {
+      "idiom" : "ipad",
+      "size" : "20x20",
+      "scale" : "1x"
+    },
+    {
+      "idiom" : "ipad",
+      "size" : "20x20",
+      "scale" : "2x"
+    },
     {
       "idiom" : "ipad",
       "size" : "29x29",
@@ -59,6 +79,11 @@
       "idiom" : "ipad",
       "size" : "76x76",
       "scale" : "2x"
+    },
+    {
+      "idiom" : "ipad",
+      "size" : "83.5x83.5",
+      "scale" : "2x"
     }
   ],
   "info" : {