update,

03_source/mobile/src/pages/DemoReactThemeSwitcher/pages/Info.tsx

@@ -1,29 +1,43 @@
 import {
   IonButton,
+  IonButtons,
   IonCardSubtitle,
   IonCardTitle,
   IonCol,
   IonContent,
   IonGrid,
   IonHeader,
+  IonIcon,
   IonPage,
   IonRow,
   IonText,
   IonTitle,
   IonToolbar,
+  useIonRouter,
 } from '@ionic/react';
 import { useGetSelectedTheme } from '../store/ThemeStore';
 import './Info.scss';
 import React from 'react';
+import { chevronBackOutline } from 'ionicons/icons';
 
 function Info(): React.JSX.Element {
   const currentTheme = useGetSelectedTheme();
 
+  const router = useIonRouter();
+  function handleBackClick() {
+    router.goBack();
+  }
+
   return (
     <IonPage>
       <IonHeader>
         <IonToolbar>
           <IonTitle>Info TS</IonTitle>
+          <IonButtons slot="start">
+            <IonButton shape="round" onClick={handleBackClick}>
+              <IonIcon icon={chevronBackOutline}></IonIcon>
+            </IonButton>
+          </IonButtons>
         </IonToolbar>
       </IonHeader>
       <IonContent fullscreen>