Smartphone users, on the other hand, said the third-most popular activity was to post and upload photos.

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When paired with an iPhone, the phone becomes both a view-finder and an accessory that lets users share video clips by email, post to Facebook or upload to YouTube in real-time.

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Faculty members at those schools have used Course Info to create fairly robust Web sites on which they upload content, manage discussion boards and chat rooms, post announcements and track what students view at the schools' Web sites, Pittinsky said.

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If you like to post or live-stream audio or video from your phone to the Internet, you probably care about upload speeds -- which means you might want to avoid Sprint, unless it offers a WiMAX network in your city.

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