Mobile phones / SIM cards ...

[Dick]

Davey
If you're not making many outgoing calls, the choice of tariff doesn't strike me as an issue. It's network location availability.
My bf tells me DTAC and GSM both have that, favouring GSM out in the styxx, and DTAC in the city. He uses 1-2-go (OK) himself because he got a deal on the tariff (years ago) when he bought it, and now keeps it going to retain his same phone number.
Apparently most of the providers offer regular tariff deals... probably best to ask your boy special (or next best thing) when you arrive, if tariff is important. I got 5b 1st minute therafter 0.25B/min on DTAC in December, but confess I let the bf phone to grill them on what was available. He chose that tariff because he tends to speak long time to his mother (on my phone!), and wanted to save me money, lol.
Everyone tells me to steer clear of Orange because they have limited network connection, and 'many friend complain no signal'.

[Brad the Impala]

Yes TOQ, that system works with 12call, GSM, TOT......the lot I think.

[Davey612]

Thanks for all your comments.

Sounds so far that AIS (1-2 go) may provide the best coverage. Maybe the best way is to get a Thai-only Sim card and buy the suggested pre-paid long distance phone cards to use when calling overseas.

As another member pointed out, U.S. travellers must have a GSM tri-band phone that is unlocked. The main two GSM systems in the U.S. are Cingular and T-mobile. I think all Cingular phones are locked while T-mobiles are already unlocked. How to unlock a phone? Go to your cell phone reseller. I had mine unlocked at a Chinatown store for $10.

I vaguely remember a message thread on the resource board for this, but it seems to have disappeared.

T-mobile mobiles are "Locked" as well. I tried putting my BFs SIM Card in my T-mobile phone while in BKK, and it wouldn't work. But as you say, it can be easily "Unlocked".