Cell Phone in Asia?
 

I will be traveling to Thailand, Malaysia, Singapore and Australia, can any one help with suggestions on what type of cell phone(s) is/are usable there? Can I rent or buy a phone at Singapore airport? I will be at each country only about 4 or 5 days.

Get a tri-band GSM. Works in all countries. Make sure the phone is unlocked when you want to use it with other SIM cards.

Either use your US card (convenient, but very expensive) or get local prepaid cards (cheaper if you make a substantial amount of calls, but less convenient).

Or get two phones. Leave on with the US Sim. See who calls (make sure voicemail and forwadring and all is off) and then call from the second phone with the local SIM. (btw. inbound calls with prepaid cards are usually free).