We’ve just walked through the process, and it went off without a hitch. If you’re interested in doing the same but don’t want to do it alone, we’ve thrown together a handy step-by-step guide, just for you.
Disclaimer: I am not your mom. I'm are also not the one who made any of this stuff, nor do I recommend doing it. There have been reports of this process bricking (read: breaking) phones, though it seems to work just fine for everyone we’ve talked to. If your iPhone breaks, melts, or runs away, or if AT&T somehow figures out you’re tethering and charges you a million dollars per megabyte, it’s not MY fault.
I'm seeing some reports on Twitter that some users are having issues with WiFi, GPS, or YouTube after unlocking with Blacksn0w. If you have any such issues, go to Settings > General > Reset> and hit “Reset Network Settings”. Once that’s complete, do a hard power cycle by holding the sleep/home button for a few seconds and then sliding the on-screen power toggle.
With that out of the way, lets begin. The entire process is drop dead simple, and should take roughly 10 minutes. This should work on both Windows and OS X. The steps below assume that you have not yet jailbroken your iPhone, and will walk you through that process.
- Download BlackRa1n for either Mac or PC here.
- Plug in your iPhone
- Run BlackRa1n
- Hit the “Make it rain” button to jailbreak your iPhone. Your iPhone 3GS will almost immediately reset, and will soon display a picture of iPhone hacker Geohot. The entire process should take about 45-60 seconds. Do not interrupt this process by unplugging the cable or tinkering with your iPhone.
- Once your iPhone has fully booted: Congratulations! Your iPhone is now jailbroken.
- Look for the Blackra1n icon on your iPhone’s homescreen. Open the Blackra1n app
- Tap the label that reads “sn0w”, then hit the Install button in the upper right. This will unlock your phone for use on any SIM-compatible carrier, and reenable the IPCC hack required to enable tethering.. This part should take about 30 seconds.
- Once the unlock is complete, open Safari. Navigate to:
- Hit the “Install” button in the upper right. Confirm the resulting prompt, alerting you that the file has not been signed. Allow the IPCC file to install, which will take about 10 seconds.
- Close Safari. Hold the sleep and home button until your iPhone resets. This reboot may take a bit longer than normal.
- When your iPhone resets, go into Settings > General > Network > Internet Tethering. If you can successfully switch the “Internet Tethering” slider to “On”: Congratulations! Everything seems to have worked as expected.
From here, tethering is a matter of following the on-screen instructions. Enjoy your jailbroken, tetherable iPhone 3G/3GS on OS 3.1/3.1.2! If you’ve gotten this far, we’d recommend installing Cydia (just open up blackra1n and tap the Cydia label). You should also consider allowing Cydia to record the signature hashes of your device once installed; be it that Apple patches this exploit in the next release, you’ll most likely need those to get back to a jailbroken state.
Also if for some reason you don't want the blackra1n icon or program on your phone, you just want tethering, you can uninstall it by simply opening the app an clicking the red line then uninstall. This will stop the ability to use the unlock feature though.