This is for those poor souls who got served a 200SGD bill from Singtel because they didn’t read my article on the dangers of getting an iPhone without a data plan or read it way too late.
To disable data on your iPhone if you don’t have a data plan, the easiest way is to install bossprefs via Cydia and turn off edge and 3G, if you have a jailbroken iPhone.
For those of you purists who rock original unmodified iPhone software, the best way is to mess up the APN settings.
Under Settings>General>Network>Cellular Data Network>Advanced, change the settings from this;
APN: e-ideas
Username:
Password:
to something like this;
APN: xxxxxx
Username:yyyyyyyy
Password: zzzzzzzzz
Remember, it is not enough if you just turn off the 3G in the settings. All it does when you turn off the 3G is to revert to Edge/GRPS in order to save battery power.
Edit: Ever since iPhone 3.0 came out, many iPhone users, particularly Starhub ones, have complaint that changing the APN settings no longer stop the 3G/GRPS data from working. The only way is to call up Starhub, and tell them that you want to cancel your GPRS service with immediate effect.