What do I mean is that I want to use the app to create a shortcut with icon on the desktop which will allow user to speed access some functions of this app.
How could I do that, any suggestions? Or anyone have experience with this.
An example: FaceDial
I spent a good while trying to implement this functionality into an app recently and wanted to put out some of the resources I found on the subject to save someone else a major headache. This is becoming an increasingly popular feature and is used in major apps like Workflow and Facebook's Groups app. Given that Workflow is now an Apple app, it doesn't look like Apple has any issues with using this technique either. The answer provided by @jin is essentially correct. The process looks something like this:
Your webserver will need to display a page which returns another page in an base64 encoded format so that the user can use the shortcut after the webserver stops running (obviously you can't leave the embedded server running 24/7). The encode page will need to detect if the page was launched in standalone mode. If it was, then it should take you to your app, otherwise it should present you with a page where the user can save the page to the homescreen. Here's a sample of how my html looked for the service:
<!DOCTYPE html>
<html>
<div id="html">
<!DOCTYPE html>
<html>
<head>
<title>Add to Homescreen</title>
<meta content="text/html; charset=UTF-8" http-equiv="Content-Type"/>
<meta content="width=device-width; initial-scale=1.0; maximum-scale=1.0; user-scalable=no;" name="viewport"/>
<meta name="apple-mobile-web-app-capable" content="yes" />
<meta name="apple-mobile-web-app-status-bar-style" content="black" />
<meta content="SHORTCUT NAME HERE" name="apple-mobile-web-app-title"/>
<link rel="icon" type="image/png" href="data:image/png;base64, ICON IMAGE DATA"/>
<link rel="apple-touch-icon" href="data:image/png;base64, ICON IMAGE DATA"/>
<link rel="apple-touch-startup-image" href="data:image/png;base64, ICON IMAGE DATA"/>
</head>
<body>
<a id="redirectURL" href="YOUR CUSTOM URL" name = "redirectURL"></a>
<script>
if (window.navigator.standalone) {
var e = document.getElementById('redirectURL');
var ev = document.createEvent('MouseEvents');
ev.initEvent('click', true, true);
e.dispatchEvent(ev);
window.close();
} else {
document.write("<center><h1>Valet</h1><img id=\"imageIcon\" src=\"data:image/png;base64, IMAGE ICON DATA\"></img><h2> Add this page to your homescreen </h2></center>")
}
</script>
</body>
</html>
</div>
<script type="text/javascript">
var html = document.getElementById("html").innerHTML;
html = html.replace(/\s{2,}/g, '')
.replace(/%/g, '%25')
.replace(/&/g, '%26')
.replace(/#/g, '%23')
.replace(/"/g, '%22')
.replace(/'/g, '%27');
var dataURI = 'data:text/html;charset=UTF-8,' + html;
window.location.href = dataURI
</script>
</html>
Here's a list of resources on the topic that helped me out (Sorry, I don't have enough reputation to include more than 2 links... so you'll have to copy pasta these):
https://gist.github.com/FokkeZB/5899387
https://stackoverflow.com/questions/28042152/link-to-safari-add-to-home-screen-from-inside-app
http://cubiq.org/add-to-home-screen
https://developer.apple.com/library/content/documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/Inter-AppCommunication/Inter-AppCommunication.html
https://developer.apple.com/library/content/featuredarticles/iPhoneURLScheme_Reference/Introduction/Introduction.html
https://stackoverflow.com/questions/9238890/convert-html-to-datatext-html-link-using-javascript
Let me know if anyone has any questions!