diff --git a/GammaTest/AppDelegate.m b/GammaTest/AppDelegate.m
index e5a328b..00e0403 100644
--- a/GammaTest/AppDelegate.m
+++ b/GammaTest/AppDelegate.m
@@ -51,6 +51,9 @@ - (UIApplicationShortcutItem *)shortcutItemForCurrentState {
 
 - (void)updateShortCutItem {
     UIApplication *application = [UIApplication sharedApplication];
+    if (![application respondsToSelector:@selector(shortcutItems)]) {
+        return;
+    }
     UIApplicationShortcutItem *shortcut = [self shortcutItemForCurrentState];
     application.shortcutItems = @[shortcut];
 }
@@ -68,11 +71,13 @@ - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(
                                                               @"autoEndHour": @7,
                                                               @"autoEndMinute": @0,
                                                               }];
-    
-    if ([application respondsToSelector:@selector(shortcutItems)] &&
-        !application.shortcutItems.count) {
-        [self updateShortCutItem];
-    }
+
+    [self updateShortCutItem];
+
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(userDefaultsChanged:)
+                                                 name:NSUserDefaultsDidChangeNotification
+                                               object:nil];
     
     [GammaController autoChangeOrangenessIfNeeded];
     
@@ -143,4 +148,8 @@ - (void)application:(UIApplication *)application performActionForShortcutItem:(U
     completionHandler(handledShortCutItem);
 }
 
+- (void)userDefaultsChanged:(NSNotification *)notification {
+    [self updateShortCutItem];
+}
+
 @end