fully cracked Apple’s latest iPhone OS update, iOS 4.3.1(2011)

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.by taatjene, from venturebeat.com