unlock iPhone 4 ios 5 for tmobile?

Oct 16, 2011
Mission, Texas
I recently purchased an iPhone 4 and it was running on 4.3.3. and this weekend i took it to get unlocked. It turns out that the place where I took it ended up updating to ios 5 without me knowing and told me they couldnt fix it because "the Sim card wasn't fitting." When I took it to someone else they told me that they couldnt unlock it because its running on IOS 5. Can my phone be unlocked or can it "downgrade" the update?
Oct 18, 2011
I'm recently starting to understand this whole baseband/firmware/jailbreak/unlock thing, I'm from Mexico but I'm doing everyhing by myself google'in and reading a lot lol, but as far as I've learned my answer would be this:

If you had your iPhone jailbroken while it was on 4.3.3 and you saved the SHSH, you can go back to 4.3.3; HOWEVER, you can't unlock for now since the person who updated you to iOS 5 most likely didn't preserve your baseband (it seems he had no idea what he was doing since you mentioned he said it was your sim card and accidentally updated to iOS 5) and baseband isn't downgradable (only firmware). I know that there's no software (ultrasnow or somethig like that) nor hardware (gevey sim) compatible with iOS 5 baseband yet. It seems you need to wait until new software releases appear for you to unlock your iPhone running iOS 5.

I pretty sure I'm right but if someone who is really experienced can confirm this it'd be most appreciated.


Senior Moderator
Dec 12, 2008
No, the baseband cannot be downgraded and you won't be able to use the iPhone software unlock (ultrasn0w). Your only option at this time is a GEVEY SIM card unlock. Then you can cut your standard size T-Mobile SIM down to micro SIM size so it fits in the iPhone 4.


New Member
Oct 30, 2011
just had that issue recently, the baseband was upgraded to 4.11.08, i was able to downgrade the IOS (so that i can still use it as an iPod touch :( ), i've looked everywhere and no answer, i guess we just need to wait for the dev team to come up with a fix or workaround... :(