Hey guys, today im going to show you step by step on how to jailbreak your iPhone 3GS running 4.1 on your Mac OS X based (or hackintosh) computer. This method will also work on the iPhone 3G. *DISCLAIMER* I am not responsible for anything that goes wrong on your device. This is for educational purposes only.
Before we start: Make sure you are running on 4.1! This will also work with 4.2.1 but if you have a new bootrom you will have a tethered boot! Meaning you have to connect it to your computer every time you need to reboot! 4.1 is UNTETHERED. Meaning you don’t have to connect every time you reboot, it will just reboot normally. Also this is for people that do NOT need to unlock their iPhone.
Restore to 4.1 via iTunes. This is not required, although I recommend it. BACK UP EVERYTHING FIRST IF YOU DO!
If you get error 1015, Google and download RecBoot, open RecBoot Exit, and then click “Exit Recovery”
After you’ve set up your iPhone, open up Redsn0w. iTunes will quit, only because redsn0w forces it to. Don’t be surprised if it does.
Click browse, and select the 4.1 firmware you downloaded earlier.
If you are using a 3GS, you will get this popup. Select “yes” if you have a new bootrom, “no” if you have an older one.
Now let’s go ahead and select what options we want. This may look different if your bootrom is new.
Follow the instructions to enter DFU mode to let it work it’s magic.
After this you will get code across your screen, but this is normal.
Congrats! You now have an iPhone 3GS (or 3G) on 4.1 jailbroken!! You should have Cydia on your homescreen. That is where you get all your jailbroken themes, ringtones and more.