How to check if iPhone 3GS is factory unlocked

[jcandrada]

I bought yesterday a used iPhone 3GS. The iPhone works with any SIM card great, and it doesn't have CYDIA nor INSTALLER nor BlackRa1n app installed. If I turn it off and then on again, it keeps working just fine with my SIM. It has currently iPhone OS 3.1.2.
Is there a way to check if this iPhone is Factory Unlocked?

 

[labman]

If it's factory unlocked

It doesn't need to be jb or unlocked hense the word factory. Easiest way is pop another sim in say your AT&T pop in a tmobile if it reads it it's unlocked. It will also say unlocked in iTunes. If you bought the phone in say the us then it's not factory unlocked. The phone would have to bought from country that has factory unlocked phones. In which case the warrenty is only good there.

 

[FatJaun]

Unlocked? on 3.1.3

I too have purchased an Iphone described as unlocked. It is on firmware 3.1.3.
It works with tmobile orange and Vodafone sims. Can I safely believe it unlocked and connect to itunes etc?

Thanks for any help. I already have a 3.1.2 iphone that I have JB'd and blackra1n unlocked. There is no sign of such software on this phone (the 3.1.3.)

Thanks for any help.

 

[feelyou]

it has not yet emerged a jailbreak for iPhone 3.1.3

 

[jcandrada]

Ok, it seems that the phone I bought (I bought an used iPhone 3GS) is from AT&T (MB716LL/A) so it shouldn't be Factory Unlocked then... but still any sim cards work on my iPhone, but I don't see any signs of any softwares used to unlock it or signs of it being jailbroken... how is this possible? is there a way to unlock an iPhone without leaving any softwares on it?? I'm asking this because I want to update my iPhone to iOS4 and I don't want it to be locked...