During the holiday season, many organizations are soliciting donations of old cell phones to be repurposed. This is an excellent way to "reuse, reduce, and recycle" and puts those useless (to you) items to use in a positive way, but please remember -- important and private data reside in your cell phone's internal memory, even if your phone has a removable SIM card. PINs, passwords and other critical information are often stored in a cell phone's memory. The more mobile apps you use, the more important it is for you to ensure that you wipe the cell phone internal memory before donating, trading-ins or selling.
Some tips -
1) Don't forget to remove the SIM card!
2) Call logs, photos, memos, and other information might reside in the phone's internal memory, and are often difficult to delete if you rely on the phone's manual (and who keeps those, anyway??). The folks at ReCellular - a cell phone recycling service - have a great solution called The Cell Phone Data Eraser. It lets you choose the brand and model number of your phone, and then displays the precise commands you need to delete every piece of data from it. The ReCellular website is http://www.recellular.com/recycling/data_eraser/default.asp. If you can't find the info you need here, most cell phone manuals are available online at the manufacturer website for download.
If you think you can circumvent the privacy threat by sending your phone back to your service provider, you could be mistaken. According to one report, a Cingular customer who received a refurbished phone as a replacement for one that malfunctioned found the new phone was filled with the previous owner's private data, including account numbers, user names, and passwords. In December, an old BlackBerry sold at a McCain campaign garage sale for 20 dollars was found to be preloaded with a mountain of Republican donor information, emails, and more.
Don't let this discourage you from turning those paperweights back into useable technology for folks who need it -- just take some extra time to protect your personal information.