IE9 Mobile Developer Overview

One of the most common questions that we field from web developers is “what does your browser support?”, or conversely “does your browser support ‘x’?”. The goal of this post is to answer those questions by outlining the advancements in the IE9 Mobile web platform and providing pointers to more detailed information.

It’s IE9!

As previously mentioned, as part of the Mango release we unified the code base for Internet Explorer across Windows and Windows Phone. This enabled us to make a huge leap forward in the platform, taking advantage of all of the latest and greatest work done in the Internet Explorer web platform.

It also means that the simplest way to answer the questions in the intro is: “It supports what IE9 supports!”. It also means the commitment to high-quality, interoperable implementations of Web standards (aka “same markup”) carries through to Windows Phone.

New web platform features in IE9 Mobile

In case you’re not familiar with recent advancements in Internet Explorer, here is a laundry list of new capabilities in the Mango web platform over what was provided in Windows Phone 7.

  • HTML5

    • Audio
    • Canvas
    • DOM Storage (Web Storage)
    • Geolocation
    • Selection APIs
    • Semantic Elements
    • Video
  • CSS
    • CSS 2.1 compliance
    • CSS3 2D Transforms
    • CSS3 Backgrounds & Borders
    • CSS3 Color
    • CSS3 Media Queries
    • CSS3 Namespaces
    • CSS3 Values and Units
    • CSS3 Selectors
  • DOM
    • DOM Core (L2 and L3) and Views (L2)
    • DOM Element Traversal
    • DOM L2 and L3 Events
    • DOM L2 HTML
    • DOM L2 Style
    • DOM L2 Traversal and Range
    • Enhanced DOM
    • Mutable DOM Prototypes
    • Selectors API
  • ECMAScript 5
  • SVG 1.1 (Second Edition)
    • Most document structure, interactivity and styling
    • Basic shapes
    • Filling, stroking, marker, color
    • Patterns
    • Paths
    • Text
  • XHTML5
  • Miscellaneous
    • Cross-domain request (XDR)
    • Data URI support
    • Native JSON support
    • SVG in HTML

While that is a long list (whew!), it is actually not a complete one (for the sake of keeping this blog post to a reasonable length). For a more comprehensive look at the platform support in IE9 Mobile, simply refer to the following Internet Explorer documentation (the real beauty of having the same platform is shorter blog posts!), minus a few specific sections which I’ve called out below the links:

Mobile-specific platform features in IE9 Mobile

As you can see from the list above, the web platforms across PC and phone are essentially the same. However, in order to provide a great mobile web experience, the IE9 Mobile platform supports the following capabilities that are not present on IE9 for Windows:

  • <meta name=”viewport”> support: this tag is used to set the width and other properties on the browser viewport. See our previous post or the MSDN article linked below for more details.
  • -ms-text-size-adjust support: this CSS property is used to control the scaling applied to text on webpages to make it more readable.

You can read more details about mobile-specific behaviors and differences in the Web Development for Windows Phone topic on MSDN.

Just the beginning!

This post serves as a high-level overview showing the big improvements to the IE9 Mobile web platform in Mango. In upcoming blog posts, we will be diving into much more detail on these new capabilities. Also keep in mind that IE9 on Windows and Windows Phone share much more than just Web standards support – from security features to fully GPU-accelerated HTML5 using DirectX graphics APIs. More details to come on that front too!

Charles Morris
Program Manager Lead, Windows Phone