title: url_launcher: canLaunch / launch don't work on iOS for simple URL scheme?
body: <p>I'm using url_launcher: ^5.4.10 for launching different url scheme but is that external link is working fine on ios simulator but not working opening phone dialpad and default email address while its working fine on android devices</p>
  <p>i tested it on ios simulator not real device</p>
  <p>if i  try to open dialpad here is exception</p>
  <pre><code>{PTS: 6.000 s, decode: 32.021 ms},
  ]
  flutter:  could not launch tel:+18002509646
   
  </code></pre>
  <p>when i try open email box here is exception i received</p>
  <pre><code>*** First throw call stack:
  (
  0   CoreFoundation                      0x00000001084f4a2a __exceptionPreprocess + 242
  1   libobjc.A.dylib                     0x00000001083874ce objc_exception_throw + 48
  2   Foundation                          0x0000000107f2e808 -[__NSConcreteURLComponents initWithString:] + 0
  3   CoreServices                        0x000000010f7c2db2 -[_LSURLOverride initWithOriginalURL:checkingForAvailableApplications:] + 136
  4   CoreServices                        0x000000010f7c35b5 -[_LSURLOverride initWithOriginalURL:] + 22
  5   CoreServices                        0x000000010f7c3d97 _ZN14LaunchServices12URLOverridesL20getURLOverrideCommonEP5NSURL + 374
  6   CoreServices                        0x000000010f7c3c10 -[LSApplicationWorkspace(LSURLOverride) URLOverrideForURL:] + 12
  7   UIKitCore                   &lt;…&gt;
  </code></pre>
  <p>my code url launcher</p>
  <pre><code>import 'package:flutter/cupertino.dart';
  import 'package:flutter/material.dart';
  import 'package:auto_size_text/auto_size_text.dart';
  import 'package:flutter/services.dart';
  import 'package:url_launcher/url_launcher.dart';
  
  class Contactcus extends StatelessWidget {
    void customLaunch(command) async {
      if (await canLaunch(command)) {
        await launch(command);
      } else {
        print(' could not launch $command');
      }
    }
  
    @override
    Widget build(BuildContext context) {
  
      return Scaffold(
        body: SingleChildScrollView(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: &lt;Widget&gt;[
              Padding(
                padding: EdgeInsets.only(top: 10),
                child: Container(
                  child: Column(
                    children: &lt;Widget&gt;[
                      Text(
                        'Contact us'.toUpperCase(),
                        style: TextStyle(
                          fontFamily: 'TT NORMS',
                            fontWeight: FontWeight.w100,
                          fontSize: 25,
  
                        ),
                      ),
                      Padding(
                        padding: EdgeInsets.only(left: 0),
                        child: Row(
                          children: &lt;Widget&gt;[
                            Expanded(
                              child: SizedBox(
                                child: ListTile(
                                  leading: Icon(Icons.phone,
                                      size: 25, color: Colors.black87),
                                  onTap: () {
                                    customLaunch('tel:+18001569647');
                                  },
                                  title: Text(
                                    'Phone'.toUpperCase(),
                                    style: TextStyle(
                                        fontFamily: 'TT NORMS',
                                        fontSize: 20,
                                      fontWeight: FontWeight.w100,
  
                                    ),
                                  ),
                                  subtitle: Text(
                                    '1 (800) 250-9646 ',
                                    style: TextStyle(
                                        color: Colors.black87,
  
  
                                    ),
                                  ),
                                ),
                              ),
                            ),
                          ],
                        ),
                      ),
                      Padding(
                        padding: EdgeInsets.only(left: 0),
                        child: Row(
                          children: &lt;Widget&gt;[
                            Expanded(
                              child: SizedBox(
                                child: ListTile(
                                  leading: Icon(Icons.email,
                                      size: 25, color: Colors.black87),
                                  onTap: () {
                                    customLaunch(
                                        'mailto:livinghopetv@cornerstoneasianchurch.com?subject=Feed%20back&amp;body=Write your%20feedback');
                                  },
                                  title: Text(
                                    'Email',
                                    style: TextStyle(
                                        fontFamily: 'TT NORMS',
                                        fontWeight: FontWeight.w100,
                                        fontSize: 20
                                    ),
  
                                  ),
                                  subtitle: Text(
                                    'livinghopetv@cornerstoneasianchurch.com',
                                    style: TextStyle(color: Colors.black87,
  
                                    ),
                                  ),
                                ),
                              ),
                            ),
                          ],
                        ),
                      ),
                      Padding(
                        padding: EdgeInsets.only(left: 0),
                        child: Row(
                          children: &lt;Widget&gt;[
                            Expanded(
                              child: SizedBox(
                                child: ListTile(
                                  leading: Icon(Icons.location_on,
                                      size: 28, color: Colors.black87),
                                      onTap:(){
                                      customLaunch('https://www.google.ca/maps/place/3434+Cawthra+Rd,+Mississauga,+ON+L5A+2X7/@43.6025224,-79.6147441,17z/data=!3m1!4b1!4m5!3m4!1s0x882b470c94e668ff:0x62c956c363a795d9!8m2!3d43.6025185!4d-79.6125554');
                                      },
                                  title: Text(
                                    'MAILING ADDRESS',
                                    style: TextStyle(
                                        fontFamily: 'TT NORMS',
                                        fontWeight: FontWeight.w100,
                                        fontSize: 20
  
                                    ),
                                  ),
                                  subtitle: Text(
                                    'Att: Living Hope TV\n'
                                    'Cornerstone Asian Church\n'
                                    '3434 Cawthra Rd\n'
                                    'Mississauga, ON L5A 2X7\n'
                                    'Canada',
                                    style: TextStyle(
                                        color: Colors.black87,
  
                                    ),
                                  ),
                                ),
                              ),
                            ),
                          ],
                        ),
                      ),
  
  
                      Padding(
                   padding: EdgeInsets.only(top: 70),
                        child: Row(
                          mainAxisAlignment:MainAxisAlignment.center,
                          children: &lt;Widget&gt;[
                            IconButton(
                              icon: Image.asset('images/youtube.png'),
                              iconSize: 30,
                              onPressed: () {
  
                         customLaunch('https://www.youtube.com/channel/UCsnohhaCJvkT3prNnMwlvnA');
                              },
                            ),
                            IconButton(
                              icon: Image.asset('images/twitter.png'),
                              iconSize:30,
                                  onPressed: () {
                          customLaunch('https://twitter.com/livinghopetv1');
  
                              },
  
                            ),
                            IconButton(
                              icon: Image.asset('images/instagram.png'),
                              iconSize: 30,
                                  onPressed: () {
                          customLaunch('https://www.instagram.com/livinghopetv/');
  
                              },
  
                            ),
                             IconButton(
                              icon: Image.asset('images/facebook.png'),
                              iconSize: 30,
                                  onPressed: () {
                          customLaunch('https://www.facebook.com/livinghopetelevision');
  
                              },
  
  
                            ),
                             IconButton(
                              icon: Image.asset('images/web.png'),
                              iconSize: 30,
                                  onPressed: () {
                          customLaunch('https://www.livinghopetv.org');
  
                              },
  
  
                            ),
  
                          ],
                        ),
                      )
                    ],
                  ),
                ),
              ),
            ],
          ),
        ),
      );
    }
  }
  </code></pre>