In Reply to: Warning if using iPhone in Bali posted by Tina G on Tuesday, 27. September 2011 at 11:16 Bali Time:
you will not be 'roaming' and not get a bill back home. However, you might still want to adjust your settings. The first time I used a smart phone in Indonesia, over night my 50,000 credit was gone as it downloaded work emails - which of course I didn't want anyway. I changed the setting so I had to manually fetch emails.
Using a local sim means you don't have to turn off your internet or 3G, which can be handy.