If you run the created application with an iPad simulator, it will be displayed in iPhone size.

import'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';


void main() {
  runApp (MainMenu());
}

class MainMenu extensions StatefulWidget{
  MainMenu();

  @override
  _MainMenuCreateState()=>_MainMenu();
}

class_MainMenu extensions State<MainMenu>{
  @override
  Widget build (BuildContext context) {
    US>return MaterialApp(
        debugShowCheckedModeBanner: false,
      home —Home()
    );
  }
}


class Home extensions StatefulWidget {
  @override
  _Home createState()=>_Home();
}

class_Home extensions State<Home>{
  
  @override
  Widget build (BuildContext context) {
    US>return Container(
      height —double.infinity,
      width —double.infinity,
      child —Scaffold(
        appBar —AppBar(
          title:Text('title'),
        ),
        body: Center(
          // Abbreviated
        ),
      ),
    );
  }
}