While your cell phone has a lot of handy built-in features, you may be unaware of some of its lesser known functions. Whether you want to disguise your phone number when making calls or shed some light in the dark, simple codes and tricks can extend the usefulness of your cell phone.
To see the serial number of your phone, enter "*#06#" and hit the "Send" key. Your phone will then display the serial number (write down and save this number in case you ever call technical support and they ask for it).
To block your outbound caller ID, press "*67" before dialing a number. Restricting your outbound caller ID will cause "Unknown Number," "Restricted Caller" or "Private Number" to show on the recipient's screen rather than your phone number.
Many other codes are available but dependent on the model of phone that you have. Performing an Internet search for "Motorola phone codes" or "Nokia secret codes" can reveal a lot of unexpected functions that your device is capable of.
Power Cycling Trick
Turning your phone off and then back on once per day is an effective form of preventative maintenance. Cell phones are very similar to their computer counterparts and need to be periodically reset to work properly. Power down your phone by holding the red "End Call" key until it shuts off. Hold the key in once more to power the phone back up. Some phones have a dedicated power key, so look for this if the "End Call" key does not work.
Because your cell phone gives off a lot of light from the display, it can be used a flashlight if necessary. Simply flip your phone open or activate the screen in the dark. If you are using an iPhone, BlackBerry or Android device, search the application store for programs that turn your phone's camera flash into a flashlight.