Think all your sensitive personal data is gone from your phone once you perform a factory reset and wipe? A new study from security firm AVAST may make you think again.
Recently, the company purchased 20 used Android smartphones. All of the devices had been factory reset or otherwise wiped by their former owners. But despite that, AVAST was able to recover a wealth of intensely personal information ranging from loan applications, emails and even photos of the phones’ previous owners – minus their clothes.
“From just 20 phones, we found over 40,000 pieces of very personal information,” says AVAST Mobile President Jude McColgan. “Selling your used phone is a good way to make a little extra money, but it’s potentially a bad way to protect your privacy.”
Of course, it’s hard to justify letting a gently used smartphone that could fetch hundreds of dollars depreciate to $0 sitting in a junk drawer. If you want to sell your device, you can minimize your risk by installing mobile security software that overwrites your data instead of just erasing it. AVAST’s own free avast! Anti-Theft app offers this capability, as do a small handful of other free and subscription-based offerings, including Andro Shredder (free) and iShredder 3 PRO ($3.29). You can also connect your phone to your computer and manually shred files using your computer's file shredding program. We like File Shredder (free) for Windows PCs and Permanent Eraser (free) for Macs.
For more on protecting the personal data on your phone, read our need-to-know guide on mobile security.