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iLoyal

macrumors regular
Original poster
Nov 18, 2010
175
1
Hi, can someone please tell me how to know if a iphone 4 is factory unlocked or not?

Thanks
 
Umm, I am buying it from another person and he told me it's factory unlock.
 
Try a foreign unsupported sim and make sure its not JB and unlocked.

Why would a foreign sim make a diff? When it is jb-unlocked it is supposed to work with any sim.....unless you are clued in to something I am not.. which I hardly think is the case... by your 'assertion', jailbreak-unlock methods would then have to vary by country/carrier - which is not the case
 
Why would a foreign sim make a diff? When it is jb-unlocked it is supposed to work with any sim.....unless you are clued in to something I am not.. which I hardly think is the case... by your 'assertion', jailbreak-unlock methods would then have to vary by country/carrier - which is not the case

Read the thread again genius.
Because the phone in question is supposed to be factory unlocked.
Not jb and software unlocked.
Big difference.
 
Read the thread again genius.
Because the phone in question is supposed to be factory unlocked.
Not jb and software unlocked.
Big difference.

And to you 'genius' any non ATT sim would suffice... is my point. Because you made a point to say: "Try a foreign" and my response to that is: Why would a foreign sim make a diff? IF he is in the US, which he very well may be, he can use any non att sim. Using a foreign SIM to test would not make any difference in the outcome, if testing just by swapping and using SIMs.

And IF he is in the the US he would have to find a micro sim thats not ATT... good luck with that... he would be better off just getting a random SIM or buy one and cut it with a SIM cutting tool if needed...and test it.

You are a 'genius' indeed, so do explain when one is testing using a non att sim, foreign or otherwise, what would the difference be.. outcome wise? I am all ears.
 
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The OP didn't explicitly say s/he was in the US. Also, applejuiced could've been using the alternate definition of foreign.

To answer the original question: use a sim that's not a carrier for the iPhone. If you live in the US, cut a t-mobile down to size. When you're meeting the seller in person, look for the modem baseband. If it's 2.10 or higher, it's definitely factory unlocked. If it's 1.59, you'll have to look for any signs of jb. Look at the iOS version. If it's iOS 4.1+, it's likely jb. If you still can't tell, go to erase all content and settings. JB and software unlocks can't survive this process. Granted, the seller will probably beat you up after, because you screwed up their chance to pawn off a software unlock as factory; but screw their lying ass anyway. ;)

And to you 'genius' any non ATT sim would suffice... is my point. Because you made a point to say: "Try a foreign" and my response to that is: Why would a foreign sim make a diff? IF he is in the US, which he very well may be, he can use any non att sim. Using a foreign SIM to test would not make any difference in the outcome, if testing just by swapping and using SIMs.

And IF he is in the the US he would have to find a micro sim thats not ATT... good luck with that... he would be better off just getting a random SIM or buy one and cut it with a SIM cutting tool if needed...and test it.

You are a 'genius' indeed, so do explain when one is testing using a non att sim, foreign or otherwise, what would the difference be.. outcome wise? I am all ears.
 
This is probably a dumb question...but, what's the difference between a canadian iphone that's unlocked vs a US iPhone locked?

so lets say for instance you unlock the US iPhone via jailbreak...you basically software unlock it and a restore to factory setting locks it again.

now, is there anything in the software that locks it? if so, can one just download whatever version canadians get off the server and install it onto the US iPhone?

here's wishful thinking...
 
This is probably a dumb question...but, what's the difference between a canadian iphone that's unlocked vs a US iPhone locked?

so lets say for instance you unlock the US iPhone via jailbreak...you basically software unlock it and a restore to factory setting locks it again.

now, is there anything in the software that locks it? if so, can one just download whatever version canadians get off the server and install it onto the US iPhone?

I know it's early, but do you think people would be spending 1,000s of hours working on a software unlock if all they had to do was install software meant for a Canadian phone?

Unlocking has nothing to do with the level of iOS you're running, except that Apple packages the baseband and iOS updates together. Otherwise, you couldn't keep your baseband the same and upgrade iOS. Also, the baseband isn't changed every time iOS is.

The baseband is the code running on the hardware inside the phone that talks to the cellular network, i.e., the modem. Obviously, the modem has to communicate with iOS and the SIM. I imagine it's one, or more, of these connections that the software unlock hacks to unlock the phone.

I am guessing that it's the baseband that checks the carrier encoded on the SIM with the carrier encoded and encrypted in the baseband. On a locked phone they have to match.

More technical people will have to explain how a factory unlock works because clearly factory unlocked phones can receive and install baseband updates without becoming locked.
 
I know it's early, but do you think people would be spending 1,000s of hours working on a software unlock if all they had to do was install software meant for a Canadian phone?

Unlocking has nothing to do with the level of iOS you're running, except that Apple packages the baseband and iOS updates together. Otherwise, you couldn't keep your baseband the same and upgrade iOS. Also, the baseband isn't changed every time iOS is.

The baseband is the code running on the hardware inside the phone that talks to the cellular network, i.e., the modem. Obviously, the modem has to communicate with iOS and the SIM. I imagine it's one, or more, of these connections that the software unlock hacks to unlock the phone.

I am guessing that it's the baseband that checks the carrier encoded on the SIM with the carrier encoded and encrypted in the baseband. On a locked phone they have to match.

More technical people will have to explain how a factory unlock works because clearly factory unlocked phones can receive and install baseband updates without becoming locked.

Trust me, i'm aware that a ton of people have spent countless hours making an unlock. I'm just really curious how a company can keep a device locked so easily this day and age. I mean, we have brilliant people working on the code to make the unlock, i'm suprised they haven't broke the code to type in a one time unlock code. just thinking too far into it i'm sure.
 
Trust me, i'm aware that a ton of people have spent countless hours making an unlock. I'm just really curious how a company can keep a device locked so easily this day and age. I mean, we have brilliant people working on the code to make the unlock, i'm suprised they haven't broke the code to type in a one time unlock code. just thinking too far into it i'm sure.

I'd bet the issue is the baseband has lots of security and encryption included, it's not the code that's complicated.
 
And to you 'genius' any non ATT sim would suffice... is my point. Because you made a point to say: "Try a foreign" and my response to that is: Why would a foreign sim make a diff? IF he is in the US, which he very well may be, he can use any non att sim. Using a foreign SIM to test would not make any difference in the outcome, if testing just by swapping and using SIMs.

And IF he is in the the US he would have to find a micro sim thats not ATT... good luck with that... he would be better off just getting a random SIM or buy one and cut it with a SIM cutting tool if needed...and test it.

You are a 'genius' indeed, so do explain when one is testing using a non att sim, foreign or otherwise, what would the difference be.. outcome wise? I am all ears.

Foreign unsupported sim meaning a non official carriers sim card genius.
I didn't mean go and find a sim from a foreign country.
I'm done responding to your posts.
Get a clue first before you post any more junk posts.
 
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Thanks for all the helpful response!
Purchased 5 Factory unlocked IP4 White edition yesterday by convincing the seller to open all iphones out of the box and restored the iphones, then tested with T-mobile sim. Not to mention the cheap price that I paid! ^^

You Mac geeks rock!
 
Thanks for all the helpful response!
Purchased 5 Factory unlocked IP4 White edition yesterday by convincing the seller to open all iphones out of the box and restored the iphones, then tested with T-mobile sim. Not to mention the cheap price that I paid! ^^

You Mac geeks rock!

Wow, nice:D
And they were all white iphone 4's?
Definately after a restore and with a Tmobile sim you're pretty much solid they are factory unlocked.
Good luck with them and congrats on the purchase.
 
Wow, nice:D
And they were all white iphone 4's?
Definately after a restore and with a Tmobile sim you're pretty much solid they are factory unlocked.
Good luck with them and congrats on the purchase.

Yea, all of them is white iphone 4's and it's a package deal so I paid about 450ea. But they should definitely find/design a way to identify factory unlocks. Like a special code or something.
 
Foreign unsupported sim meaning a non official carriers sim card genius.
I didn't mean go and find a sim from a foreign country.
I'm done responding to your moronic posts.
Get a clue first before you post any more junk posts.

jdaniel's point still stands. You can unlock then hide Cydia, inserting any SIM foreign SIM would give the same results as popping the SIM in to a factory unlocked phone.

So your method doesn't prove factory unlock, as jdaniel said.
 
best way I know of plug it snyc it with Itunes with a sim in it. you should see the fallowing. (Congratulations your iPhone is Unlocked)
 
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