What do numbers really mean in the mobile market?

Back to school. Three words designed to strike dread into the hearts of children in the U.K., particularly when they appear emblazoned all over shop displays from approximately three minutes after the start of the school holidays in July. (Much like the appearance of foil-wrapped Christmas chocolates in the supermarkets sometime in August, but don't get me started on that...)It's finally here though. Sad-faced youngsters are making their final preparations for the return to education next week,