"In this case study we want to help designers and developers who are familiar with iOS to reimagine their apps using Metro style design principles. We show you how to translate common user interface and experience patterns found in iPad apps to Windows 8 Metro style apps," explain the case study authors in their introduction.
A Windows 8 contract, as Microsoft describes it, "is like an agreement between Windows and one or more apps. Contracts define the requirements that apps must meet to participate in these unique Windows interactions." Developers of Metro-style apps -- a k a WinRT-based apps -- are encouraged to make use of these contracts.
App to app picking: Designed to "help users pick files from one app directly from within another app"
Play To: Helps users play digital media to connected DLNA devices from within an app
Search: Adds a search pane to an app "so users can search not only your app's content but content from other apps as well," according to Microsoft's description. "Users can also transfer the search query itself to other apps."
Settings: Provides in-context access to settings that affect the user's experience with an app
Share: Meant to help users share content from your app with another app or service, and vice versa. "Participating in the Share contract means that you don't have to write extra code or provide other developers with an SDK for your app just to share content," Microsoft officials explained.
There is also an "HTML5 community night" event on April 10 at Microsoft Mountain View. These are focused on open-source projects using HTML5. They look a lot like the original Microsoft Mix events, with participants from Adobe, Google, Mozilla and Microsoft on the docket. The three-hour event also will be Webcast, according to a blog post from a Microsoft developer evangelist.