Lighthouse Pwa

• Add an Apple touch icon to your Progressive Web App

Add an Apple touch icon to your Progressive Web App

{% include 'content/devtools-headsup.njk' %}

Safari for iOS users can manually add Progressive Web Apps (PWAs) to their home screen. The icon that appears on the iOS home screen when a PWA is added is called the Apple touch icon. This codelab shows you how to add an Apple touch icon to a PWA. It assumes that you have access to an iOS device.

{% Aside %} iOS Safari users can add any webpage to their home screen. It doesn't have to be a PWA. In fact, the example app used in this codelab isn't a PWA. But in most cases a PWA would be the kind of app that a user would most likely want to add to their home screen. {% endAside %}

Measure

Open the example app in a new tab:

{% Instruction 'remix', 'ol' %}

{% Instruction 'preview', 'ol' %}

1. Note the URL of your example app. It'll be something like https://example.glitch.me.

Run a Lighthouse PWA audit on your example app in Chrome DevTools:

{% Instruction 'audit-pwa', 'ol' %}

In the PWA Optimized section, Lighthouse reports that the example app doesn't provide a valid Apple touch icon.

{% Img src="image/tcFciHGuF3MxnTr1y5ue01OGLBn2/MTeobnXovn2UGJW1lhQ9.png", alt="Does not provide a valid apple-touch-icon", width="800", height="283" %}

Add the example app to an iOS home screen

To demonstrate how an Apple touch icon provides a more polished user experience, first try adding the example app to your iOS device's home screen when an Apple touch icon hasn't been specified.

1. Open Safari for iOS.
2. Open the URL of your example app. This is the URL like https://example.glitch.me that you noted earlier.
3. Tap Share {% Img src="image/tcFciHGuF3MxnTr1y5ue01OGLBn2/79A8XsdBaHeLGY5Wdm1J.png", alt="Apple Share Button", width="46", height="60", style="height:1.2em;width:0.92em;vertical-align:top;" %} > Add to Home Screen. You'll probably have to swipe left to see this option.
4. Tap Add.

Because the site hasn't specified an Apple touch icon, iOS just generates an icon for the site from the page's content.

{% Img src="image/tcFciHGuF3MxnTr1y5ue01OGLBn2/mjkYYf7Fjpm4EwzMJ7Xc.png", alt="An auto-generated home screen icon.", width="640", height="1136" %}

Add an Apple touch icon to the example app

• Uncomment the <link rel="apple-touch-icon"> tag at the bottom of the <head> of index.html.

    …
    <link rel="stylesheet" href="/index.css">
    <link rel="shortcut icon" href="https://cdn.glitch.com/49d34dc6-8fbd-46bb-8221-b99ffd36f1af%2Ftouchicon-180.png?v=1566411949736">
    <!-- <link rel="apple-touch-icon" href="https://cdn.glitch.com/49d34dc6-8fbd-46bb-8221-b99ffd36f1af%2Ftouchicon-180.png?v=1566411949736"> -->
    <link rel="apple-touch-icon" href="https://cdn.glitch.com/49d34dc6-8fbd-46bb-8221-b99ffd36f1af%2Ftouchicon-180.png?v=1566411949736">
  </head>
  …

Add the example app to an iOS home screen (again)

• Try adding the example app to an iOS home screen again. This time, a proper icon is generated for the site. If you audit the page again with Lighthouse you'll also see that the Does not provide a valid apple-touch-icon audit now passes.

{% Img src="image/tcFciHGuF3MxnTr1y5ue01OGLBn2/Z8nauimUFUDPY8HJDGER.png", alt="The Apple touch icon.", width="640", height="1136" %}