Owners of Apple's new iPhone 4S consume twice as much data as iPhone 4 users, and triple that of iPhone 3GS owners, a U.K.-based network management firm said today.
After analyzing traffic on a unnamed European mobile carrier, Arieso concluded that the iPhone 4S was the biggest contributor to a boost in data consumption in 2011 over the year before.
Arieso, which counts mobile network providers O2, Telefonica and Vodofone among its clients, said that iPhone 4S users download an average of 276% more data than people with an iPhone 3G, Apple's 2008 smartphone.
On the data upload side, iPhone 4S users beat iPhone 3G owners by 320%.
Apple started selling the iPhone 4S in the U.S. and several other countries -- including the U.K., France and Germany -- on Oct. 14. Since then, Apple expanded iPhone 4S availability to dozens of other markets, and plans to roll out the device in China a week from today.
Altogether, iPhone 4S owners consumed three times more data than iPhone 3G users, and double that of people with an iPhone 4, Apple's 2010 model, said Arieso.
While the company could measure data use for individual smartphone models, it wasn't able to pinpoint the exact kind of bits that were being transmitted or received. "The drill-down causes are not directly available to us," admitted Michael Flanagan, Arieso's chief technology officer and the author of his company's report, in an interview today. "So we have to look at the feature capabilities of the phones."
So Flanagan attributed the iPhone 4S' voracious appetite to a pair of causes.
"The most salient difference between the iPhone 4S [and earlier models], and we think the root cause, is its cloud-based capabilities," said Flanagan.
He cited the constant synchronization via iCloud -- Apple's sync and storage service that also is accessible to users of the iPhone 4 and iPhone 3GS -- as one, and Siri, the voice-activated assistant available only on the iPhone 4S, as the other feature most likely to cause increased data consumption.
iCloud's synchronization means more data on the download and upload channels, said Flanagan, especially when that data consists of audio and video files.
"Say I download the latest "Archer" episode from iTunes to my laptop," he said. "The next day it's been automatically downloaded to my iPhone. And if I take videos using the iPhone, it's automatically pushed to another device via iCloud. Together [the downloads and uploads] can account for the increases."
Siri, which some reports identified as the most likely reason why iPhone 4S data consumption was double that of the iPhone 4, is probably also a cause, Flanagan said.
"It's not exclusively Siri, but it is a major component, maybe even the dominant one," said Flanagan.
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