First, today we are releasing the Windows Phone Developer Tools Update (please be patient as the CDNs are updated). This update will allow developers to build apps using some updated assemblies which will ship in the forthcoming Windows Phone OS update. In practical terms, this is the tools update that supports the forthcoming addition of copy and paste, improved app performance and other enhancements for Windows Phone. All apps which are in Windows Phone Marketplace will continue to work on any phone that gets updated to the new version of the OS. Any app built using this new version of the tools will also work on phones that have not been updated to the new OS. (quick links: WPDT update & Visual Studio update – you need them both, and Release Notes).
Second, while the majority of all apps will work just fine, we do encourage every developer to open their projects with the updated tools and do a sanity check on their projects. Most apps will not need to be recompiled or resubmitted. All apps will benefit from the changes made in the forthcoming OS update, resulting in performance increases, as well as copy/paste functionality for your customers who update to the new OS.
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