Specific sequences of characters, typically beginning with an asterisk or hash symbol, provide access to hidden menus and diagnostic information on Apple’s mobile operating system. For example, a code might reveal signal strength in decibel-milliwatts or display call forwarding settings.
These numerical or symbolic commands serve a vital function for technicians and power users needing to diagnose issues or configure device settings beyond the standard user interface. Originally designed for internal testing and engineering, their continued availability allows for advanced troubleshooting and customization not typically exposed to the average user. Their existence dates back to the initial releases of the mobile OS, reflecting a legacy of embedded diagnostic capabilities.