Toyota is the first major company to begin advertising on Cydia, one of the main Web stores for jailbroken apps. The car company launched a Scion 2011 Theme now available for download through Cydia for the iPhone. Toyota is also running an ad campaign through ModMyi, another jailbreaking site on Cydia.

While jailbreaking your phone can void your warranty, it is legal. Jailbreak apps can offer some functionality that official apps from Apple’s online App Store don’t. For example, there’s a jailbreak app that lets users use FaceTime over 3G instead of restricting it to wi-fi, as the official app does.

In a blog post from ModMyi, another jailbroken app site, the site’s founder and owner Kyle Matthews said that this could represent a major shift toward legitimizing the jailbreak community.

“There's a giant market which is being largely ignored,” he wrote. “Cydia is awesomely poised to be a great avenue for say, Flash. If a user chooses to jailbreak their device, so be it. Or even better - if no jailbreak was needed and Apple shipped a device we could fully access just like all our other computers.

Today the iPhone Dev Team, a group that specializes in jailbreaking iPhones, released an untethered jailbreak for the latest iOS, 4.3.1. (An untethered jailbreak doesn’t require you to reboot while connected to an external device.) The hack, redsn0w, works with all current iOS devices except the iPad 2.

Some users who’ve downloaded the latest version of redsn0w are reporting problems with FaceTime and Wi-fi connections.

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