How can I open/redirect my flutter app to open the default recorder app on the phone?

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

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

class MyApp extends StatefulWidget {
@override
 _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
@override
void initState() {
 super.initState();
}

Color containerColor = Colors.red;

@override
Widget build(BuildContext context) {
return MaterialApp(
  home: Scaffold(
    appBar: AppBar(
      title: const Text('Plugin example app'),
    ),
    body: Center(
      child: Container(
        height: 50,
        width: 150,
        child: RaisedButton(
            color: Colors.blue,
            onPressed: () async {
              await LaunchApp.openApp(
                androidPackageName: 'net.pulsesecure.   pulsesecure',
                iosUrlScheme: 'pulsesecure://',
                appStoreLink:
                    'itms-apps://itunes.apple.com/us/   app/pulse- 
 secure/id945832041',
                // openStore: false
              );
              // Enter thr package name of the App you  want to open and 
for iOS add the     URLscheme to the Info.plist file.
              // The second arguments decide wether the     app 
redirects PlayStore or AppStore.
              // For testing purpose you can enter com. 
instagram.android
            },
            child: Container(
                child: Center(
              child: Text(
                "Open",
                textAlign: TextAlign.center,
              ),
            ))),
        ),
      ),
    ),
  );
 }
}

For more information, check out this answer: How to open another app using flutter Youtube Tutorial:Flutter Tutorial - Open Apps, Launch Urls in Flutter