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Resolved Question

A few questions about unlocked phones

by Dec 15, 2012 4:03AM PST

I want to just start off by apologizing if this either incredibly obvious or if this is the wrong place to post this, but I cannot for the life of my find answers to these questions.

Hello! I'm considering buying an unlocked cell-phone and I have a few questions about them.

1) I currently have at&t and I have a locked galaxy s2 with a sim card. can I use that sim card on an unlocked phone, even though it came from a locked phone?

2) Can an unlocked cell-phone be used without a sim card? From what I have heard, they can be used without the sim card, you just can't do anything that uses 3g/calling/texting/etc...

3) I'm wanting to get an xperia Play unlocked phone, and as far as I can tell they don't have a locked version for at&t. will this have any affect on whether or not the unlocked one will work with at&t?


If anybody has any answers to these questions, I would be grateful if you helped me. Thanks in advance!

Discussion is locked

Jumbosize3 has chosen the best answer to their question. View answer
4 Posts
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Best Answer

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Don't be afraid to ask....
by Forum moderator Dec 15, 2012 5:27AM PST

1. You can swap your SIM card between compatible devices and keep the same phone number.
2. You cannot use a GSM phone without an active SIM card for anything but 911 calls.
3. As long as the device operates w/ the 850 and 1900 mhz frequencies and is unlocked, it should work with At&t.

If you have further questions, don't hesitate to ask.

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Thanks!
by Jumbosize3 Dec 15, 2012 5:47AM PST

Thank you very much, I really appreciate your help. However, I do have a question about your answer to the second question. On my current phone, (At&t Samsung Galaxy S2) I can take out the SIM card and use it just fine as long as I don't try to make calls or anything. If I'm not mistaken this is a GSM phone, right?

So are you sure this would be the case? Again, I know very little about this topic so I could easily be wrong...

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Answer
by birdmantd Forum moderator Dec 15, 2012 8:09AM PST

You cannot make calls or access cellular data without a SIM card installed in the phone (with the exception of 911). There is absolutely no question about that.

You could use wifi on the phone without a SIM but that is because the phone has the hardware built in and does not involve the cellular carrier. You can use the built in features/applications in the phone without a SIM that do not require a cellular connection.

If you are using an At&t phone, it is definitely GSM technology.

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Thanks again
by Jumbosize3 Dec 15, 2012 8:25AM PST

Ahh, that clears things up. I was under the impression that you were saying literally the only thing you could do with the phone was dial 911. I appreciate your help.

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