Original URL: http://www.theregister.co.uk/2010/02/18/silverlight_mobile/

Microsoft banks Windows Phone 7 on Silverlight

Downsizing a big opportunity?

By Gavin Clarke

Posted in Developer, 18th February 2010 06:02 GMT

Microsoft's Flash-challenging Silverlight media player could be the hidden secret driving Windows Phone 7, the Redmond mobile OS unveiled this week.

Silverlight will be named the platform for building native applications in Windows Phone 7 and future generations of Windows Phones at next month's Mix conference, unnamed sources have told CRN.

Hoopla and hype of this week's debut aside, the actual technology details on Windows Phone 7 have been vague. Microsoft has not said what the operating system is under the covers.

Redmond has been careful to position this latest rev of its software and phones as "Windows Phone 7" and not Windows Mobile 7 - which is what everyone had been calling it prior to this week as it was the successor to Windows Mobile 6.5. For what it's worth, Microsoft also offers Windows CE for mobile devices.

Instead, Microsoft has told people to simply wait for more details during its annual Mix web and media development conference in Las Vega, Nevada.

Significantly, Microsoft is not sharing any information ahead of that event through the Mix web site, with all sessions on mobile carrying the same "More to come. Stay tuned," message. The company has not outlined what to expect from sessions on Silverlight.

If Silverlight is destined for Windows phones, it's been a long-time coming.

In 2008, Microsoft promised The Reg that Silverlight for mobile would arrive in the first-quarter of 2009 along with manufacturers porting Silverlight to and distributing Silverlight with Windows and non-Windows mobile devices. Only Nokia has committed, with the S60, as Microsoft has kept working on Silverlight for mobile.

Silverlight serving as Microsoft's platform for mobile has it's advantages. It would certainly support the kind of slick and polished interface for Windows smartphones Microsoft's chief executive Ballmer showed off, with buttons, sliders, touch and gesture for video, and audio and data-based applications. The current experience of Silverlight provides scaling, cropping, streaming, and crystal-clear deep zooming on pictures and text on the PC.

Silverlight 3, released last year, delivered the ability to work offline and run outside the browser without an additional download. It also offered support for touch-based input that's also been a feature of Windows 7, along with a set of new data-oriented grid controls. This came with the existing ability to detect bandwidth for stutter-free streaming and support for the H.264 and Advanced Audio Coding (AAC) audio.

Silverlight fits into Microsoft's belief in what it calls the "natural user interface." This interface idea includes support for manipulation and gestures, ideas that have been put on the mobile map by Apple's iPhone.

Microsoft's runtime has plenty of attraction for Microsoft developers already targeting PCs and servers, developers who are potentially interested in mobile. Silverlight lets you re-use existing skills and code, as Silverlight apps are coded using Microsoft's Visual Studio.

Reg reviewer Tim Anderson wrote last year that Silverlight 3 is closer to what client-side .NET should have been: lightweight, high-performance, cross-platform, and supported by a rich graphical user interface framework that takes a sane approach to layout.

But there are some un-answered questions that complicate the notion of Silverlight becoming the runtime for Windows phones and that Microsoft would need to tackle.

The big question is whether Microsoft would let Silverlight become just like its Windows operating system or even Adobe's AIR. That is: Will Redmond let its media player and interface technology talk to the hardware and draw on local data, turning Windows phones into more than just phones but pocket-sized computers?

In some ways, this is a part of larger question inside Microsoft of how far it should take Silverlight, which sprung of the Windows Presentation Foundation (WPF) for PCs. Should Silverlight be bulked up into a pseudo operating system that developers program to instead of Windows?

Interestingly, Microsoft will use Mix to draw a distinction between Silverlight 4 and WPF 4 Touch APIs at Mix.

Ubiquity, once more

Furthermore, there's the question of whether Microsoft will actually allow Silverlight to run on more non-x86 platforms - specifically ARM, which dominates mobile computing. In the PC world, Silverlight can talk to PowerPC in addition to x86 to run on Windows and Linux.

Also, there's the issue of application ubiquity - the Nirvana of the fragmented handset market. As a downloadable runtime, Silverlight can potentially run on a large number of devices by providing a consistent interface and set of APIs. That would mean Silverlight applications also run on a greater number of phones than is possible with the current Windows Mobile, which is pulled and pushed to work on different handset hardware and that relies on OEMs to ship it into the market.

With Silverlight 4, which is already in beta, there are signs that when it comes to the PC Microsoft is starting to tailor its player to machines running Windows. It's doing that using Internet Explorer and COM.

Already, Windows Phone 7 devices are displaying signs of lock-in - only at a hardware level, as phones will feature a back and a Bing button. The question is how far features like these tie into Silverlight and constrain the ability of applications written for Silverlight to run on different handsets without the need for modification by the developer.

Finally, as in most important matters, there's the matter of size: Silverlight is a 5MB download that takes up to 10 seconds. That's still too big and too slow for mobile, something even Microsoft noted ruefully when it released the Silverlight 4 beta last November.

Silverlight as a platform for native applications on Windows mobile phones has plenty of appeal for the user and developers. The only thing standing in its way is Microsoft - and how far the company's willing to go.®