AT&T Consistently Overcharges for Data Use: Suit Investigators left iPhones unused for 10 days in probe By Matt Cantor, Newser User Posted May 20, 2011 10:32 AM CDT 1 comment Comments In this April 28, 2011 photo, a customer holds a white iPhone at the Apple store on New York's Upper West Side. (AP Photo/Richard Drew) (Newser) – AT&T “systematically” overcharges customers for data usage on their iPhones and iPads, a probe finds. In a lawsuit, investigators say the firm overcharges by 7% to 14% on a regular basis—and that charges have in some cases reached up to 300% of what they should be, the Daily Mail reports. In the study, AT&T overcharged for “every single” transaction, says a lawyer. Investigators left brand-new iPhones unused for 10 days, with all internet-accessing software turned off. But their bill charged for 35 transactions. Engineers measured the quantity of data downloaded to determine the overcharging percentages. AT&T called the charges “without merit,” saying they “reflect a misunderstanding of the way data is measured.” Consumers, the firm says, may not realize the amount of data used in automatic updates and background processes.