Privacy Rights Clearinghouse
It may not seem like common sense to clean your trash before you throw it away, but with technology that is exactly what you should do.
Before you sell, donate or trash your cell phone, make sure that your personal information has been permanently deleted. For most phones, this means more than resetting the phone. Although resetting the phone may appear to delete your information, recent reports suggest that software programs can retrieve the information if it was not properly deleted.
To properly delete your personal information you need to follow the steps listed in your phone manual for “safely deleting” or “permanently deleting”. The instructions often involve complicated or repetitious key strokes. If you are not confident that the instructions offer the type of security you are looking for, call your phone company and ask about their data deletion procedures. The web site Recellular provides a handy deletion guide for most cellular phone models: www.recellular.com/recycling/data_eraser/default.asp  .
According to Trust Digital, a mobile security software company, many phone manufacturers use “flash” memory chips to store information. These chips are similar to those used in digital cameras and some music players.
Manufactures welcome this type of memory chip because it is inexpensive and durable. However, it takes longer to permanently erase information.
Owners of expensive phones, such as Blackberries, Treos and other PDAs, are more likely to try and resell or give away their old models. Unfortunately, these phones tend to contain sensitive personal data, including client contact information, e-mails, spreadsheets and other files.
If you work for a large corporation, consider talking to someone in your Information Technology department about how to properly delete sensitive information.
Owners of simpler cell phone models may want to avoid the problem altogether by not storing sensitive information on your phone. Although it may seem convenient to type in your account numbers and passwords, most people do not own cell phones for longer than a few years. Since your cell phone is small and easily stolen or lost, it may not be the ideal place to keep passwords, account numbers, and other valuable information.