Tips & Advice

How to thoroughly wipe your phone before selling it

Deborah Salmi, 17 July 2015

How to thoroughly wipe your phone before selling it

Make sure your Android phone is wiped clean before you sell it.

Every day, tens of thousands of people sell or give away their old mobile phones. We decided to buy some of these used phones to test whether they had been wiped clean of their data. What we found was astonishing: 40,000 photos including 750 photos of partially nude women and more than 250 male nude selfies, 750 emails and texts, 250 names and addresses, a collection of anime porn, a complete loan application, and the identity of four of the previous phone owners.

How did we recover so much personal data?

The problem is that people thought they deleted files but the standard features that came with their operating system did not do the job completely. The operating system deleted the corresponding pointers in the file table and marked the space occupied by the file as free. But in reality, the file still existed and remained on the drive.

With regular use of the device, eventually new data would overwrite the old data but since the person was selling the phone, that never happened and the files were still intact.

It works the same way on your PC. I used free software to recover deleted photos that I thought were missing forever because they had not been overwritten yet.

You can permanently delete data with Avast Anti-Theft

Avast’s free app for Android, Avast Anti-Theft, actually deletes and overwrites all of your personal files. All you do is follow these steps to delete personal data from your smartphone before you sell it or give it away.

1. Install Avast Anti-Theft on your Android device. The app is free from the Google Play Store.
2. Configure Avast Anti-Theft to work with your My Avast account. This gives you remote access to your phone through your PC.
3. Turn on the thorough wipe feature within the app.
4. Log in to your My Avast account from a PC to wipe your phone. This will delete and overwrite all of your personal data.

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