iPhone "jailbreaking" has been a hot topic since Apple released its smartphone more than two years ago. While the amazing little device does indeed have applications for "just about everything," Apple's sometimes arbitrary or self-serving rejections of apps such as Google Voice has turned more people on to the idea of freeing themselves from dependence on Apple for these resources (and also, in some cases, from AT&T for a network signal).
A collective of hackers known as the iPhone Dev-Team publishes easy-to-use, cross-platform tools that allow you to install third-party apps on your iPhone that Apple won't admit into its App Store.
For the moment, however, the legality of jailbreaking is in question. The Dev-Team offers its free tools without any proprietary code so as not to violate copyright laws. But Apple recently filed a statement arguing that jailbreaking constitutes copyright infringement because it incorporates a modified version of Apple's bootloader, the software that loads the main operating system.
Some jailbreakers are mostly interested in using their iPhones on a network other than AT&T's. Using a different network with your iPhone may get you better coverage, save some money on your data plan, or help when you're traveling overseas, but don't expect any tech support from Apple or AT&T. Unlike jailbreaking limited to loading third-party apps, jumping to a different network is not completely reversible, because of the changes it makes to the phone's baseband (modem firmware). The legality of this kind of jailbreak is even more questionable.
Suppose you're interested in a relatively simple jailbreak to experience third-party apps. This has some definite advantages, but some cautions to consider as well.
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