**Editor's note: Please click here for our list of February's hottest selling smartphones to see how the iPhone 5 stacked up against the competition or here for a breakdown of some of the most egregious bill-shock moments of all time.
Australian iPhone users recently had to pay a steep price for excessive data downloads – an issue reportedly caused by Apple software problems.
All three major Australian phone carriers confirmed a large amount of complaints and bill shock after the launch of the iPhone 5 in that country, according to a Herald Sun article. Some iPhone email users also recently reported an issue with data draining.
The specific problem: Some users' phones showed that they were using a Wi-Fi connection when they were not, which led to heavy mobile data use. A similar issue happened with Verizon iPhone customers in the U.S. shortly after it launched in September.
Spokespeople for Vodafone, Optus and Telstra recommended that users update their iPhone software in order to prevent unexpectedly high bills. The companies also refunded charges on a case-by-case basis.
"We monitor our network very closely and where unusual data usage is identified we will contact our customers to ensure they are aware and to understand the cause,'' said a Vodafone spokeswoman.
Apple's most recent software update, iOS 6.1.3, was released last week and addresses both issues that users were facing.