Microsoft officials promised more details about the company's Windows Phone 7 development strategy would be revealed in mid-March at its Mix 10 conference. But those details already have begun to leak out.
Not surprisingly, Silverlight is at the crux of Microsoft's development platform. XNA, Microsoft's game-development platform, also is part of the puzzle.
According to documents posted to the XDA Developers Forum and surfaced more widely by WMPoweruser.com, Microsoft will make available a limited set native application programming interfaces (APIs), with the the real focus on managed APIs (meaning .Net-based). The primary tools for developing for the Windows Phone 7 OS will be Visual Studio 2010 and Microsoft Expression Blend (a design tool for Silverlight and .Net), according to the docs.
The XNA Framework, an implementation of the .Net, and its associated tools, also are likely to be part of the mix. Given the XNA Game Studio already supports Xbox 360, as well as the Zune media player, -- and Windows Phone 7 borrows so liberally from the Zune HD, in terms of its user interface) -- it makes sense XNA tools will support Windows Phone 7. For the record: Microsoft officials have declined to say whether Zune HD apps and games will run on Windows Phone 7 -- and whether new Windows Phone 7 apps will run on Zune HDs.
I've heard a few more specifics from a couple of my contacts who've asked me to keep them anonymous. One described Microsoft's Windows Phone 7 planned developer pitch as follows:
"The dev platform is Silverlight 3, plus elements of 4, using Blend and a Visual Studio add-in. The kicker is that while it is XAML-like, it is not pure XAML (Extensible Application Markup Language). This is actually OK, as it keeps the footprint nice and small.
"In theory you can make an entire app inside of Blend, but I think you will need Visual Studio to hook it all together in C#. In the war vs. Apple for apps, every .NET developer just became a Phone developer."
Microsoft has yet to announce officially (or make available to external testers) the promised add-on(s) for Visual Studio 2010 that will support Windows Phone development. One of my sources said there will be one tool that will be integrated with the Visual Studio 1020 integrated development environment (IDE) and another that will be available as standalone install. Microsoft officials have said they'll have more to say about mobile-development support for Visual Studio 2010 some time this year. (Mix 10 is my guess.)
WMPoweruser points to the newly leaked documents (which Microsoft isn't confirming are real, but sure look as though they are) as proving that Windows Phone 7 will enable multitasking. I'm still not 100 percent convinced of this, as I've heard from my contacts that Microsoft will be playing fast and loose with what "multitasking" means with Windows Phone 7 so as to be able to claim that's the case. (The aforementioned source gave me a pretty definite 'no' when I asked whether Windows Phone 7 would support multitasking to the same degree that Windows Mobile 6.x devices do.)
Another developer issue that still remains murky is whether and how easily the existing Windows Mobile 6.x application base (1,245 apps in the Windows Marketplace for Mobile store, plus countless custom apps) will be able to run on Windows Phone 7 devices. It's obvious because of user inteface differences, existing apps will need to be modified to some degree to work. But Microsoft officials also have refused to provide details about the backward-compatibility story, saying more will be shared at the Mix show.
On a related note, for those developers still interested in writing apps for the Windows Mobile 6.x platform (for whatever reasons), Microsoft released this week a developer toolkit for Windows Mobile 6.5.3.