My own thoughts: I can see how mobile phone users might appreciate the ability to turn their small touch screen into a larger one, especially when looking at photos or watching videos.

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During their earnings call, the social network reported 618 million daily users accessing Facebook on their mobile phone, out of a total 1.1 billion daily users (I suspect some nice rounding errors there), but how people use Facebook on their mobiles is different to the desk-bound usage, and reduces their value to advertisers.

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