IE9 for Windows Phone Mango in the Spotlight

This week in New York, Andy Lees introduced Windows Phone “Mango” to the world, which includes IE9 Mobile. This announcement and associated demos built upon last month’s MIX11 conference, where Joe Belfiore demonstrated our latest progress on bringing Internet Explorer 9 to Windows Phone during his keynote address. IE9 Mobile represents a huge jump forward for us on the mobile platform, effectively unifying our underlying code base for the browser with the desktop version. In this post, I’d like to outline some of the main principles we’re following as we build IE9 Mobile.

Hardware-Accelerated HTML5 and Graphics

As Joe (or “JoeB”, as we like to call him) showed during his keynote, we’re taking advantage of the hardware available to us on the phone to ensure a high-performance experience for the user. We’ve also incorporated our brand-new “Chakra” JavaScript engine, which provides another level of performance boost to your Web applications.

This bump in performance means that you, as a Web developer, can create great sites for the mobile Web that perform like native applications and give users a rich, immersive experience. We expect that mobile HTML5 applications are going to build on this foundation and deliver game-like interactivity and movie-quality graphical richness to the user experience. We built IE9 to anticipate the rise of these modern, high-performance Web applications by using the phone’s hardware to accelerate all the graphics and text that gets drawn on the screen.

Joe’s demo showed that we’re already off to a great start in the area of performance, and we’re excited to see how developers will use this great performance to drive the mobile Web forward.

Great Support for HTML5

Speaking of HTML5, it is clearly quickly gaining traction, but nowhere is that happening more quickly than in the mobile arena. In a somewhat ironic twist thanks to the relative youth of most modern mobile browsers, it’s much more likely that a mobile user’s device will have the capabilities to support many of HTML5’s features, and IE9 on Windows Phone is no exception.

As Joe showed in the keynote, we’ve built in great support for HTML5 Audio, Canvas, and Video. Just like native applications, our audio stream will continue to play in the background when the browser is not the front-most app. We’ve even integrated support for HTML5 audio with the phone’s volume and playback controls, giving the user a nice integrated experience that they expect on Windows Phone 7.

But we’ve also paid close attention to the under-the-covers stuff, like DOM Local Storage, the DOMContentLoaded event, support for the new semantic markup elements, etc. that you need to make your Web pages sing in the HTML5 era.

Same Markup

We’re focused on the principle of “same markup” – that is, you shouldn’t have to write a whole bunch of custom code to get your mobile Web sites to look and work well on IE9 on WP7. By using established modern standards such as HTML 4/5, CSS 2/3, and ECMAScript 5, you can create mobile-optimized Web sites that work great on a variety of browsers, including ours.

To accomplish this, we are implementing accepted Web standards that are stable and site-ready inside of IE9 Mobile. In places where specifications are incomplete or ambiguous, we are looking to other implementations. This is very similar to how we approached CSS2.1 in IE8 – we delivered a high quality CSS implementation by sticking to the standard, and we are going to continue along this path to make mobile HTML5 applications easier to write and maintain.

Even in cases where a Web site has not been tuned for the mobile scenario, it will still look and work well on IE9 Mobile, given our increased support for standards and the work we’ve done to provide great rendering experiences for desktop sites on Windows Phone.

Support for Key Mobile Features

Of course, we also have to focus on the fact that IE9 on Windows Phone has to function well as a mobile Web browser application and developer platform. To that end, we’ve included full support for CSS3 Media Queries, support for using GPS when working with Geolocation, and some mobile enhancements for layout (like controlling text scaling) and the Viewport. We’ve even changed the way we render our form elements to look more like native “Metro”-styled controls to ensure that users have a consistent experience across native applications and Web sites.

The browser user interface has changed too, in order to devote more of the available screen real estate to your sites. We’ve collapsed the URL edit field and refresh button down into the Application Bar, which allowed us to get rid of the top status bar and allow your sites to really shine through.

MIX was Just the Beginning

Now that we’ve shown what IE can do when a great team of developers puts it on a phone, we’re looking forward to seeing what you can do with it. We’ll have much more information to release soon – tools for the next version of Windows Phone will be available shortly, and we want to hear your feedback. It is our goal and mission to make IE Mobile a great Web developer platform, and you are a key piece of that puzzle. Our inbox is always open – send us feedback, let us know what you like and would want to see improved, and tell us about your sites!