Thank you very much for your interest in UI for Windows Universal. A Calendar is definitely in our plans as it plays an important role in our cross-platform offering. With Q3 2014 (October) we will release it for the Windows 8.1 part of universal windows apps. Soon after will make it truly universal so it can be used in Windows Phone 8.1 applications.
I was wondering if you could share what kind of components you'd need for your Windows applications. Our product roadmap is driven by customer feedback so I'd be glad if you could share what types of applications are you building/planning to build for Windows Store.
I'd be glad to continue the discussion further.
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