A bunch of hackers, which claim to have developed the first software-based unlocking tool for the Apple iPhone, have finally made their application available – for a price.

A coupe of weeks ago, the iPhoneSIMFree group claimed to have built an application that can unlock the iPhone so it can be used on any GSM network worldwide.

But another group, which made a similar claim at the same time, received a warning letter from Apple’s lawyers, apparently creating an air of caution around the iPhone hacking community. Whereas UniquePhones held off from releasing their hack, iPhoneSIMFree have bitten the bullet and released it to a network of distributors and resellers.

The hack retails for around £40 in the UK and claims to leave all features of the iPhone intact, with the exception of the Visual Voicemail feature, which needs back end support from the operator, in this case, AT&T.

The hack has been verified by a number of independent parties but the developers have a disclaimer, which basically states that the method is not foolproof and Apple could conceivable come up with an update that disables the hack.

However, once you’ve bought the application, the developers do say that all future updates, which may be able to outwit Apple further, will be free.

Update: It seems that the iPhoneSIMFree hackers have had their party crashed by another team, which began offering its own iPhone software unlock for free on Tuesday night.

The iUnlock tool does require a bit more technical jiggery pokery than the iPhoneSIMFree version but on the other hand, it’s free.