Ok,so I've done my research here and there,and I just have this one question that keeps bugging.Let's just say that I were to get an iPhone 3G(hopefully soon),how would I go about jailbreaking it?As of now,I am running on T-Mobile using another phone,I'm also aware about the whole issue about yellowsnOw not working after upgrading to 2.2.1.Would I first jailbreak it,then download yellowsnOw via cydia,and then use my T-Mobile sim card or what?Please help.Thanks.
I would advise you to go for a jail breaking version software. There are many standard jail breaking softwares. Buy one which offers continuing support and unlock your Iphone.
Those are the 2 main jailbreaking software programs that people use. I have used quickpwn 3 times and it has worked perfectly each time. But i would recommend quickpwn over all of the other programs that you could use. If you use quickpwn it will automatically install the installer and cydia on your phone.
yellowsnow WILL still work with 2.2.1... the prob is with baseband 2.30. When you upgrade to 2.2.1 you automatically without a choice upgrade to baseband 2.30. My 3g is running 2.2.15h11 (latest) and I jailbroke it and unlocked it. Using it on Tmobile right now. I had to downgrade from 2.30 to 2.28, only possible with bootloader 5.8 or older. so to sum things up if you want upgrade to 2.2.1h11 then create a firmware with pwnagetool. Then use quickpawn to jailbreak, add yellowsnow and voila you are unlocked. If your phone is made after the 36th week of 2008 then you probally have bootloader 5.9 and MUST use pwnage tool to create your 2.2.1 firmware. If you phone was made prior to the 37th week of 2008 then you have an options. Such as upgrading to 2.2.1 with itunes and downgrading your baseband with phaseband, then jailbreak, then unlock.