Let me give this a nod.
SPB was the GO TO company when Windows Mobile still had a pulse.
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Frankly, Windows Mobile was "almost there" somewhere about 5.x to 6.5. SPB nailed it by letting us customize the home screen and more.
WP7 and the draconian rules (just try to get your app out?) along with tossing out all the great stuff that was in WM has a lot of WM developer's heading for the land of i and droid.
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