Did you use your US iPad 3G in Europe or another country?

I bought my iPad in the UK and use it in Poand. when you place the micro sim in the iPad you will need to connect the iPad to your pc/mac and sync, then you will be prompted to download carrier settings. If you travel with just your iPad you will still need to connect to a pc/mac, do not sync, and download carrier settings

I used my UK iPad whilst in the US, however I only used WiFi. When I recently changed operators in the UK I didn't need to connect the iPad to a computer to download carrier settings.

pacsur1 wrote:
Thanks for the info, I guess I am still hoping that there could be a slight chance that if I installed a sim from say Spain while I was in the US, that I could connect to iTunes there and still leave the laptop at home?

I just rethought this, if the pad needs to download carrier info I guess there is no way it can connect to a carrier in Europe while in the US.

The important parts of the carrier info can also be input manually. This is the APN and its username/password (if any). The carrier bundles downloaded by iTunes also contain things like a 'logo' (so it won't be cut off in the title bar) but none of this is important for the iPad functioning.

So you can just go to Spain, buy the SIM, cut it down to micro-sim size (if the carrier doesn't have a micro-sim for you), input the APN settings and be on your merry way.

Oh by the way, the carrier data is downloaded from apple, not from the carrier. It does not matter where you are to get it.

Is the carrier info downloadable via wifi on the ipad from Apple? Seems like this would be the way to get around the need to connect to a mac and syncing (?).

Don't think so. I think it either has to be downloaded through iTunes on a computer or possibly may be able to be manually entered in the APN settings section.

pacsur1 wrote:
Just in case you might have an answer for this, why can I use an unlocked 3g in a different country by just inserting a chip, and nothing else?

Because that chip is the part (the only part) that authenticates you to the network. The network itself is basically the same between here and the US. The only difference is what frequency bands are in use (and iPads handle the ones we use and the ones AT&T uses).

So basically the chip says to the network 'I am user A from AT&T'. If you then want to connect to the AT&T network, the network knows 'this is my user', and will let you connect. If you were to connect with a T-Mobile SIM installed (thus saying 'I am user B from T-Mobile'), it won't let you connect. (Assuming ATT and TMO don't do roaming, in which case it will let you connect and then it knows to send the bill to T-Mobile).

The phone itself does not contain any such information. Only the SIM does. This is required by the specifications for both GSM and UMTS.

This is different for CDMA phones like Verizon and Sprint use. Those you can't switch from network to network easily. Luckily, no one else in the world (save perhaps China Mobile) uses that technology so you can't really use such a phone outside the US anyway.

pacsur1 wrote:
I guess I am missing something, if the phone I am using is unlocked and accepts the sim, why wouldn't the iPad that is supposed to be unlocked also?

It does. Who told you it wouldn't?

The only thing is you'll have to either enter the APN settings or get a carrier update from Apple (over the Internet, can be done anywhere with iTunes). If neither of those happens, you won't be able to use the internet because the iPad won't know how to do it. It will however, be connected to the cellular network. Having the SIM inserted takes care of that. If the iPad could make phone calls, this would be enough to get to that point.

To draw an analogy, it's like connecting your computer to a wireless network, but to get to the internet you need a proxy server.