Hackers have fully cracked Apple’s latest iPhone OS update, iOS 4.3.1, with a jailbreak that supports all iOS devices except the iPad 2, Redmond Pie reports.

The jailbreak, which allows users to run apps unapproved by Apple and tweak their iPhones in a variety of ways, proves yet again that hackers will always find a way to crack Apple’s security. It’s also a significant release because it’s the first fully untethered jailbreak for iOS 4.3 — which is hacker-speak for a jailbreak that works even after you reboot the device.

While this particular jailbreak is nowhere near as simple as the first iPhone 4 hack from last year, which merely required that you visit a webpage on your iPhone’s browser, the process still isn’t that difficult. You just need to upgrade your iPhone, iPad 1, or iPod Touch to iOS 4.3.1 using iTunes, apply the Redsnow hack to the update, then restore your phone using the tweaked update.

Performing a jailbreak is easy enough at this point to warrant the effort, since it will allow you to access excellent apps like Notify that offer features Apple doesn’t. In fact, I’ve grown so used to the freedom allowed by jailbreaking that I find it impossible to use my iPhone without hacking it.

According to the Dev-Team blog, the hacker group responsible for a majority of iOS jailbreaks, the untethered exploit comes from Stefan Esser, a Germany-based security researcher.

Image via Gizmodo