My brother owns an Apple iPhone 3GS with iOS version 4. He asked me to jailbreak it. What I did:
- Install iTunes 9.2 on my Windows XP virtual machine.
- For some reason the iPhone was recognized as a camera/scanner. To get Windows to recognize it as a phone, I did something similar to this. Basically, use the apple driver.
- In iTunes, right-click on the device and “Backup”.
- Go to jailbreakme on the iPhone using Safari, and the jailbreak process will take place (Cydia will be installed). After this completes, the phone is jailbroken.
- In Cydera, install OpenSSH to transfer files between the computer and the phone wirelessly. Reboot the phone.
- For tethering, this states that PDANet is probably better than MyWi.
This outlines the possibilities with a jailbroken iPhone.
Remember not to update the iPhone with any apple software until knowing that the jailbreak can be preserved.