Anecdotally, I can confirm this. My data usage is up from when I had the iPhone 5. My personal take? The device isn't consuming more data per se, but the real increase in speed and responsiveness means that I'm simply using it more. Heaven knows what would happen if I switched to a 4G network.
Apple users have been the ‘hungriest’ consumers of mobile data in the 2010, 2011 and 2012 data measured by the study (iPhone 4, iPhone 4s and iPhone 5 respectively). Last year, the report indicated a possible end to this dominance as Galaxy S III users closed the gap. But iPhone 5s usage is the most intense witnessed to date, keeping Apple users at the top of the chart.
The study found that iPhone 5s users demand seven times as much data as the benchmark iPhone 3G users in developed markets (20 percent increase on iPhone 5) and 20 times as much data in developing markets (50 percent increase on iPhone 5). Beyond the 5s, Apple products account for six of the top ten ‘hungriest handsets’, along with two Samsung products, one HTC and one Sony.