[iOS] Adding missed icon related to App Store (#1084)

diff --git a/www/docs/en/dev/config_ref/images.md b/www/docs/en/dev/config_ref/images.md
index 73f711b..b38cc01 100644
--- a/www/docs/en/dev/config_ref/images.md
+++ b/www/docs/en/dev/config_ref/images.md
@@ -180,6 +180,8 @@
         <icon src="res/ios/icon-50@2x.png" width="100" height="100" />
         <!-- iPad Pro -->
         <icon src="res/ios/icon-83.5@2x.png" width="167" height="167" />
+        <!-- iTunes Marketing Image -->
+        <icon src="res/ios/icon-1024.png" width="1024" height="1024" />
     </platform>
 ```
 ### See Also
@@ -293,4 +295,4 @@
     <icon src="res/electron/icon@2x.png" />
     <icon src="res/electron/icon@4x.png" target="installer" />
 </platform>
-```
\ No newline at end of file
+```