Not just Windows Phone is great, the phone is great as well. It's a head turner with excellent build quality. Call quality and signal reception on this phone are at least a notch or two better than all the phones I have had so far. Lumia 900 has the best screen for viewing outdoor as tested by DisplayMate and PocketLint. Windows Phone is very fast, reliable, simple to use, and yet powerful. I really like the integrations in WP as a whole with Facebook, Twitter, Microsoft Office, Outlook, LinkedIn and Xbox Live. There are many features that I like including Local Scout, People Hub, Me Hub, Pin to Homescreen, Bing Vision and Bing Music. All these integrations can help you do things fast. Imagine you can check your movie times at your favorite theater with just one tap or listen to any of your favorite radio station with just one tap, that's why I said WP is also powerful. You can read more about many features of WP here. Too lazy to explain them all :/
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