diff --git a/src/plugins/platforms/ios/qiosscreen.mm b/src/plugins/platforms/ios/qiosscreen.mm
index 65a8c21060c..b54c696f3f3 100644
--- a/src/plugins/platforms/ios/qiosscreen.mm
+++ b/src/plugins/platforms/ios/qiosscreen.mm
@@ -186,6 +186,9 @@ - (void)traitCollectionDidChange:(UITraitCollection *)previousTraitCollection
 {
     [super traitCollectionDidChange:previousTraitCollection];
 
+    if (!qGuiApp)
+        return;
+
     Qt::ColorScheme colorScheme = self.traitCollection.userInterfaceStyle
                               == UIUserInterfaceStyleDark
                               ? Qt::ColorScheme::Dark