50% of handsets sold on eBay contain personal data-18% have even worse

One source of information that the criminals are using is your old cell phone. Forensic firm Disklabs bought 50 handsets from eBay and found that half of them had some kind of personal information left on internal memory. Over 60% still listed phone numbers in the call log and 9 out of 50 contained pornography.
The Director of Disklabs, Simon Steggles, says that people should not assume that the new owner of your old phone is going to remove all of your leftover information. Steggles said, "Any data left on the phone is effectively open to the public domain. That could be as varied as intimate photos, videos and text messages … People hit ‘delete’ and think that means it is gone for ever, but that’s not the case."
Some handset manufacturers now include a mobile wipe function that will allow a phone owner to remotely wipe the handset in case it is stolen. With all of the amazing functions that you can find these days on a smartphone, owners of these devices can easily forget that even the most basic of information can make you a victim of a crime that you easily could have avoided.
source: IntoMobile