Erasing data isn't enough to prevent identity theft when recycling gadgets

If you’re selling, recycling, or otherwise getting rid of an old smart phone or tablet and think simply deleting your data is enough, you could be exposing yourself to identify theft and other violations of your privacy.

Recently, the antivirus software maker Avast reported that it was able to recover “erased” personal information from 20 Android phones it had purchased on eBay. The information included more than 40,000 stored photos, including some depicting women and men in various stages of undress, more than 750 e-mails and texts, more than 250 contact names and addresses, four previous owners’ identities, and even a completed loan application. The software manufacturer posted an eye-opening, although technical, document that shows how it recovered the data and how vulnerable digital devices are.

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This investigation is one more example of an issue we’ve been writing about for a long time: Simply deleting information from electronic devices doesn't actually remove it. To make data truly unrecoverable, it must be overwritten, or the device that contains the information, for example a computer hard drive, must be destroyed.

In the blog reporting its results, Avast recommends installing the free Avast Anti-Theft software from the Google Play store and shows how to use it to permanently delete data from Android phones.

Consumer Reports has extensive tips for permanently deleting data from digital gadgets, including smart phones and tablets, personal computers, gaming consoles, and removable media. There were 3.1 million smart phone thefts in 2013, so check out our video below for advice on how to protect your phone from being stolen and safeguard the data if it is. Finally, our guide to Internet security tells you how you can protect yourself from online threats.

—Anthony Giorgianni