The Australian arm of MVNO Virgin Mobile is to become the fourth operator to offer Apple’s iPhone 3G in the country, offering data tariffs that undercut the existing iPhone operators, reports Australian PC World. Virgin Mobile, which uses the Optus network in Australia, announced today that it will offer the iPhone 3G on 24 month contracts with data plans that are deemed more competitive than those from Telstra, Vodafone and Optus, the three other operators licensed to sell the device in Australia. Virgin Mobile is understood to be the first MVNO in the world to offer iPhone 3G, which had its global launch last month. Even prior to Virgin Mobile entering the fray, Australia was considered the most competitive iPhone 3G market. The only Australian operator not to offer the device is 3, which has publicly appealed to Apple to allow it to distribute the device and recently announced a series of data plans aimed at luring iPhone customers away from other networks.

Virgin Mobile will offer two iPhone 3G plans. The first will cost A$70 (US$66) per month and includes A$520 worth of calls and 1GB of data, while the second costs A$100 per month and includes A$520 worth of calls and 5GB of data. Optus, which currently offers 700MB of data per month for A$79, was previously considered to offer the most competitive iPhone 3G data plan in the Australian market. Apple announced separately this week that there are now more than 1,000 applications available for the iPhone and that there have been 25 million application downloads.