iPhone 4S triples your data bill -

Users of the iPhone 4s will be shocked to see their data bills rise for no apparent reason.

When the iPhone 4S came out we said that there was no discernible difference between it and the iPhone 4, besides a few more bits under the bonnet and Siri.

Ever keen to prove us wrong, it seems that Apple's newest phone chews up more than twice the data bill of the its predecessor thanks to its increasing dependence on online services like the virtual personal assistant Siri.

Telecom network technology firm Arieso told Associated Press that since Siri, which means arse in Japanese, came along consumers transfer on average three times more data than users of the older iPhone 3G model.

Data usage of the previous model, the iPhone 4, was only 1.6 times higher than the iPhone 3G, while iPad 2 tablets consumed 2.5 times more data than the iPhone 3G, the study showed.

According to Arieso the iPhone is mostly a data hog because of Siri, which is a personal assistant and search app which will tell you where to find a brothel but is too uptight to tell you where an abortion clinic is.

Of course, it's possible that people are so in love with their iPhone 4S they have started downloading much more than they used to, but three times as much is a little unlikely.

Arieso's chief technology officer, Michael Flanagan, said while he used the iPhone 4 he did not think it was sensible to buy an iPhone 4S.

"However, the data usage numbers I am seeing make me wonder what I am missing," he said. Mostly a huge phone bill.