Unable to Display Camera on DevApp on Android

I am new on the Ionic platform. Please I need help.

I’m having problems getting Ionic DevApp on Android to display the camera as demonstrated in the Build Your First App tutorial.

The app opens without problems on Firefox browser.

On index.html file, I have the following code

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="utf-8" />
  <title>Ionic App</title>

  <base href="/" />

  <meta name="viewport" content="viewport-fit=cover, width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=no" />
  <meta name="format-detection" content="telephone=no" />
  <meta name="msapplication-tap-highlight" content="no" />

  <link rel="icon" type="image/png" href="assets/icon/favicon.png" />

  <!-- add to homescreen for ios -->
  <meta name="apple-mobile-web-app-capable" content="yes" />
  <meta name="apple-mobile-web-app-status-bar-style" content="black" />
  <script src="cordova.js"></script>
</head>

<body>
  <app-root></app-root>
</body>

</html>

In the tab2.page.html file, I have the following code:

<ion-header>
  <ion-toolbar>
    <ion-title>
      Photo Gallery
    </ion-title>
  </ion-toolbar>
</ion-header>

<ion-content>
  <img>

  <ion-fab vertical="bottom" horizontal="center" slot="fixed">
      <ion-fab-button>
        <ion-icon name="camera"></ion-icon>
      </ion-fab-button>
  </ion-fab>
</ion-content>

I ran the command ionic serve --devapp but I got the following error.

[ng] [console.warn]: "Fetch is unavailable so cordova-plugin-ionic has been disabled."
[ng] [console.log]: "deviceready has not fired after 5 seconds."
[ng] [console.log]: "Channel not fired: onDOMContentLoaded"
[ng] [console.log]: "Ionic Native: deviceready event fired after 2905 ms"
[ng] [console.log]: "Angular is running in the development mode. Call enableProdMode() to enable the production mode."

DevApp on Android discovers the app, but when I click on it to open it, I only see the screen as shown below for a few seconds and then DevApp closes.

Screenshot_2019-07-10-18-13-26%5B1%5D

Screenshot_2019-07-10-18-13-14%5B1%5D

What I am doing wrong? And how do I get the app to display the camera on Android so I can be sure I am making progress on the tutorial?
Thanks for your help.

DevApp doesn’t enable cordova stuff

try connect the device with ADB and then use

ionic cordova run android --device -l