When starting to design a Windows 8 app, the most important thing to do is pick out a best-at statement. To create one, answer the question: "This app is the best app in its category at what?"
Take the time to come up with a great best-at statement because many of your decisions, from what features you build to how you lay out the content in your app will be based on it.
For more information on designing your app, please see:
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