We do it in the street, in the office, in bed and even in the bathroom: whip out our phones and chew through some mobile data. Now, the carriers reckon, we're doing it too much. Data caps have been making headlines over the past few weeks, as networks announce their pricing for - ostensibly - the new iPhone 4 but - in reality - a world in which mobile Internet appetite is exceeding supply. Out goes the promise of "unlimited" data and in come not just new, tighter caps but the "average use" statistics to justify them. So why, amid echoing reassurance that what's on offer is comfortably more than we need, do I feel like I'm only hearing half of the story?