[ronny0207]

I live in the USA, and have an unlocked iphone with T-Mobile. Will it work while traveling to the Carribean?

[lefty83]

Originally Posted by ronny0207

I live in the USA, and have an unlocked iphone with T-Mobile. Will it work while traveling to the Carribean?

I believe so, should be the same like with any ordinary triband gsm phone's..

[squaresoft]

depends how your iphone is being unlocked it has no guarantee that any sim from any country will work... If you use a turbosim etc stuffs, i think it only works on certain country or even at certain firmware (i.e. once you updated to later or older firmware, your phone may be locked again...)... But as far as I know those softwares like Ziphone, iLiberty+, or pwnage tool/winpwn... they unlock your phone almost completely that most gsm sim can be supported...

[bhz1]

Is there anything one needs to do to get a foreign sim to work, or is it plug and play?

[freakoftheindustry]

If your iPhone is "Unlocked" then it should be plug and play...

[aziatiklover]

it should work but dont forget to install allregion app support

[m600i]

What does the allregion app do? I'm curious because I'm going overseas also.

[jfmsam]

First you have to make the distinction of unlocking a phone to use any SIM from any compatible GSM provider, from unlocking your phone and traveling abroad with your own SIM.

If you plan to buy a prepaid local SIM from the country you are traveling to, make sure the provider you choose conforms to any one of the following GSM bands:
Quad-band (850, 900, 1800, 1900 MHz)

If you plan to travel with your own SIM, then make sure you enable International Roaming with your cellular provider.
Beware, International voice and data roaming can be very, very, very expensive. Choose your plans wisely and be brief when you use the phone.

App support for all regions is only suggested if you will permanently use your iPhone on a currently not supported carrier/country. It is not a must but a help specially for proper display of caller id matching data.

If your trip is longer than a few days, I'd suggest you consider buying a prepaid calling card and using land lines to call. If you must use your mobile, make sure people call you because some local prepaid SIM cards offer free inbound calls.