diff --git a/admin/tool/mobile/classes/api.php b/admin/tool/mobile/classes/api.php
index 146990c755e..4126d26f440 100644
--- a/admin/tool/mobile/classes/api.php
+++ b/admin/tool/mobile/classes/api.php
@@ -433,6 +433,7 @@ class api {
                 '$mmLoginEmailSignup' => new lang_string('startsignup'),
                 'NoDelegate_ForgottenPassword' => new lang_string('forgotten'),
                 'NoDelegate_ResponsiveMainMenuItems' => new lang_string('responsivemainmenuitems', 'tool_mobile'),
+                'NoDelegate_DarkMode' => new lang_string('darkmode', 'tool_mobile'),
             ),
             "$mainmenu" => array(
                 '$mmSideMenuDelegate_mmaFrontpage' => new lang_string('sitehome'),
diff --git a/admin/tool/mobile/lang/en/tool_mobile.php b/admin/tool/mobile/lang/en/tool_mobile.php
index f9827768955..722bd3d47ef 100644
--- a/admin/tool/mobile/lang/en/tool_mobile.php
+++ b/admin/tool/mobile/lang/en/tool_mobile.php
@@ -51,6 +51,7 @@ App help|https://someurl.xyz/help|inappbrowser
 My grades|https://someurl.xyz/local/mygrades/index.php|embedded|en
 Mis calificaciones|https://someurl.xyz/local/mygrades/index.php|embedded|es
 </pre>';
+$string['darkmode'] = 'Dark mode';
 $string['disabledfeatures'] = 'Disabled features';
 $string['disabledfeatures_desc'] = 'Select here the features you want to disable in the Mobile app for your site. Please note that some features listed here could be already disabled via other site settings. You will have to log out and log in again in the app to see the changes.';
 $string['displayerrorswarning'] = 'Display debug messages (debugdisplay) is enabled. It should be disabled.';