I am coming to thailand for a 3 week vacation. I am bringing my unlocked iPhone 4 and I would like to use it for phone calls and data with a local sim. I will mainly be in Bangkok and ubon. What company and service would you recommend? I also understand that the sim for the iphone is smaller than usual how do i get it the proper size? Thanks

Do you intend coming back here within a year?

If you do, the True prepay "Inter SIM" would suit you as it remains valid for 365 days from the last top-up, with no monthly deduction. No other SIM does this, as far as I know. Per-minute call charges are reasonable, though if you use the phone a lot a different package would be cheaper.

You can add data service to it, on a daily basis. Not sure about data in Ubon.

The SIM is widely available from 7/11 shops etc. for minimal cost (50-100B) plus top-up.

The SIM seems to be the standard size, which is the only size I have ever seen. It certainly fits my Android phone. I have no idea about Apple products though, as I would never own one.

http://www.truemove....IM-Prepay.rails