The Hidden Dangers of Selling Your Old Smartphone

Advertising Disclosure: When you buy something by clicking links on our site, we may earn a small commission, but it never affects the products or services we recommend.

Image Not Available

Seller beware: You could hand over more than just a device if you sell your old Android smartphone.

A new study by researchers from Cambridge University in England found that “wiping” an Android phone using its factory reset feature can leave a lot of sensitive information behind.

They analyzed more than 20 used Android phones purchased from eBay and phone recycling companies in the United Kingdom. The phones represented five manufacturers (Samsung, HTC, LG, Motorola and Google) and multiple versions of the Android operating system, from 2.2 (Froyo) to 4.3 (Jelly Bean).

From 100 percent of the devices, researchers were able to recover:

  • Who owned the phone
  • Installed apps
  • Contacts
  • Browsing history
  • Credentials
  • Multimedia
  • Conversations (SMS, email, chat from messaging app)

These findings are consistent with those of a study conducted by Avast last year.

The antivirus software company purchased 20 used Android phones off eBay and used “simple and easily available” recovery software to restore deleted files, according to an Avast blog post. The data that the company recovered included:

  • More than 40,000 photos, including photos of children, “women in various stages of undress” and “male nude selfies”
  • More than 1,000 Google searches
  • More than 750 emails and text messages
  • More than 250 contact names and email addresses
  • One completed loan application

To decrease your chance of identity thieves, blackmailers or others exploiting your data, consider doing the following:

  • Overwriting data: Avast’s free Anti-Theft app, which the company says has a multi-step “thorough wipe” feature, can do this. The Cambridge researchers also found overwriting a “reliable” way to sanitize phones.
  • Encrypting data with a password: The Cambridge study notes that not all phones support the ability to password-protect data, however.
  • Destroying the phone: Per Thorsheim, a cyber-security expert in Norway, tells CNN Money, “Don’t hand off your old phone. Smash it.”

If you have an Android phone, don’t miss “8 Android Hacks Every User Should Know.”

Like this story? SHARE it on Facebook!

Get smarter with your money!

Want the best money-news and tips to help you make more and spend less? Then sign up for the free Money Talks Newsletter to receive daily updates of personal finance news and advice, delivered straight to your inbox. Sign up for our free newsletter today.