Rumor has it based on several sources that Apple is set to release an unlocked GSM version of its iPhone 4 this week.

According to a June 13 Digital Trends report, “The tip comes from trusted Apple rumorist ChronicWire, who posted the tidbit late Sunday night on his Twitter feed. This would be the first time US Apple Stores sold an iPhone device that was not pre-tied to specific carriers.”

In a June 12 tweet, “Chronic Wire” posted this message: “Unlocked iPhones headed to Apple Stores for Wednesday: MC603 (16GB, Black), MC604 (16GB, White), MC605 (32GB, Black) MC606 (32GB, White)”.

The parts numbers for the unlocked iPhones revealed by Chronic Wire add credibility to the rumors, industry analysts said. a

Given that Apple is no longer exclusively offered by any one particular carrier, it is a logical progression that an unlocked version would soon be hitting the streets. Verizon began selling the iPhone in February 2011, and Sprint and T-Mobile are rumored to start sell them this year, according to a PC Magazine report.

An unlocked iPhone 4 would be able to work on any GSM network around the world with an appropriate SIM card, according to Digital Trends.

Buying an unlocked phone outright, meaning minus a contract with AT&T or Verizon, is expected to cost $599, several industry reports, including GeekSugar, said. International travelers are said to get their best bang for the buck since they can purchase or rent cheap SIM cards from the country they’re visiting “to eliminate pricey roaming fees from US carriers,” blogged Geek Sugar’s Kristy Korcz.

In related iPhone news, a pair of iPhone 4 phones will be making a trip on the last space shuttle mission to the International Space Station (ISS). “Odyssey Space Research is bragging about the app it’s developed for Apple iOS in order to aid in performing four experiments on the space station – and it’s an app you can download for yourself if you want,” reported TechZone360’s Doug Mohney.

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Erin Harrison is Executive Editor, Strategic Initiatives, for TMC, where she oversees the company's strategic editorial initiatives, including the launch of several new print and online initiatives. She plays an active role in the print publications and TechZone360, covering IP communications, information technology and other related topics. To read more of Erin's articles, please visit her columnist page.

Edited by Jennifer Russell