However, I conducted a test in which I purchased a bunch of used devices off of Craigslist and eBay to see if I could still find personal data on them. I found a startling amount of personal data, including photos, phone numbers, addresses, emails, text messages and even passwords.

While most of us would think we are safe if we do a factory reset on our mobile device, this is not always the case. On some Android phones, even though some of the phones’ owners had done a factory reset, I was still able to find data on them. Here’s how to get your devices squeaky clean:

• Wipe your phone: For mobile phones, you want to do a factory reset. The software to do this is built into the phone.
  • Android factory reset: Menu > Settings > Privacy > Factory Data Reset.
  • iPhone factory reset: Settings > General > Reset > Reset All Settings.
  • Blackberry factory reset: Options > Security Options > General Settings > Menu > Wipe Handheld.
  • Windows 7 phone factory reset: Settings > About > Reset Phone.
  • On any other operating systems or Symbian-based phones, you will need to do a search on your phone online, such as, “Phone Name, Model Number, Carrier, Factory Reset.”
  • Remember to remove or wipe any media, like SD cards or SIM cards. These are so cheap, it’s better to cut them in half with a scissors or reuse them.
  • Still unsure if you’ve gotten all your data off? Get a drill and poke lots of holes in the device and its hard drive, or hit it with a sledgehammer. This may be lots of fun, but it also may make it less saleable.