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Any price plan over $79 will include the iPhone free and Optus is giving away unlimited data downloads for the first month of sale.

Optus is also putting the phone available on 12-month contracts at higher prices. A 1-year contract on a $79 cap works out to $27 to $49 per month depending on the contract.

According to Optus, the standard $79 cap includes 700 MB of data, going down to 500 MB for the $49 cap.

However pre-paid customers will pay a premium, with an 8 GB model selling for $729 upfront and the 16 GB model will set users back $849, although Optus says it will offset this with a $400 credit bonus and one gigabyte of data downloads.