How to simulate Airplane mode? I'll be overseas and don't want to be racking up roaming or whatever other charges.  Typically I would use the Airplane mode, but I still want to be able to take photos that have the geo locations recorded.

So I want to know whether turning off Settings/Cellular/Cellular Data will take care of what I want (e.g. remove the chance that I'll be inadvertently charged for something)?  It says Cellular Data...does it mean I have to turn off Cellular Voice somewhere or does this do the trick?
Just remove your SIM. Then there's no chance of incurring any cellular charges, as you won't be able to connect to any network, but wifi and GPS should still work. (If you have a CDMA phone with no SIM then you can't roam anyway.)