When I have previously been to Thailand, I purchased cheap phones to use during my short stays. This time, since I'm moving (to Chiang Mai), I would like to use my current phone, an HTC Inspire 4G w/ ATT. True Move operates 3G on 850, so it will work on my phone.

I would like to know if it's as simple as that- plug in the sim card and go. Or do I need to unlock it or do anything else?

Thanks, technologically advanced friends.

google:

unlock HTC Inspire 4G

and google will reference some sites to give you a code to legally unlock your phone for a fee. It is easy to do, there is even a youtube video on the steps.

It is hard to find out the cost before hand. There are some things in the fine print, such as servers for the different carriers may be slow at certain times.

I haven't used any of these services as i have an iPhone 4s unlocked by my carrier for free, except for the monthy payments for service.

Are you a customer in good standing with AT&T? I think that if you have been with them for six months or longer they will give you an unlock code by telling them you are traveling to Thailand.

http://androidforums.com/inspire-4g-support-troubleshooting/277826-how-does-one-unlock-htc-inspire-4g.html

http://forum.xda-developers.com/showthread.php?t=957559

http://www.howardforums.com/showthread.php/1721972-UNLOCK-HTC-INSPIRE-4G-How-to-Unlock-your-HTC-Inspire-4G-from-At-amp-t-by-Code

http://forum.xda-developers.com/archive/index.php/t-955570.html

I sure am. I've had service with them for 11 years. Thanks for all the info.