IPhone Secret codes are available here, these codes will work on the iPhone 3 or 4, most of them are actually service codes which do not work in all countries and regions.
There you have it, all the codes available for the iPhone. Much like Android there really are not that many interesting secret codes since the operating system can and does expose the bulk of the features already. If you have any other interesting iPhone secrets or hacks please e-mail them and I will add them here.
| *3001#12345#* | Enters Field mode which allows you to access most of the hidden settings and functions of your iPhone |
| *#06# | Display the IMEI of your iPhone, as always this is the standard code for all brands of phones. |
| *225# | Displays the account balance for postpaid contracts |
| *777# | Displays the account balance for prepaid accounts |
| *646# | Displays the remaining minutes available |
| *3282# | Get your data usage information |
| *729 | Options to make payments |
| 611 | Dials customer service, (114 in RSA for Vodacom) |