You could access numerous useful iPhone features by typing in a few secret codes on your device. Lots of the codes work whether you have an old or new iPhone and they can let you do things like ...

Other than *67, of course, there are plenty of codes you can enter into your iPhone's dialer to get info on your bill, your ...

Coders have a storied tradition of creating back doors in programs (or sometimes just fun little Easter eggs) that can only be accessed with a special "key." This has happened for almost as long as ...

Use these codes to forward calls, pay your bill, check balances, etc. Some of the codes work only on certain carriers or devices. One of the codes also might erase your data, so use with caution. I've ...