Before you sell, donate or discard your Android smartphone or tablet, you probably enter the system settings and restores factory data, sometimes marking a box so that all of your personal files are deleted. In theory, this operation prevents the next owner to have access to any sensitive or embarrassing given. The problem is that doing just that is not enough.
How so? Well, you should have heard something similar on the HD of your computer. When you delete a file from recycle bin, the file is not deleted from the truth: it is only “marked” as deleted so that the area of the HDD can be overwritten again with another file. If there is no overwriting of data, the file can be recovered with the numerous recovery software available out there.
It was natural that happen in smartphones and tablets, but a study of Avast , that the virus, made it clearer the problem: 20 Android smartphones they bought used on eBay, used a generic tool available publicly (the AccessData FTK Imager), and were able to recover more than 40 000 photos, 750 emails and SMS, contacts 250 and identification data from four previous owners. Among the more than 40 000 photos retrieved, it should be clear that any potentially embarrassing: 250 selfies were of naked men. Not the kind of photo that its owners would like to slosh around. And as much as our own life, but also of our work, you can go through the smartphone, unauthorized access to data can cause major damage.
How to avoid the new owner to recover your data then? Explains how the CNET , the best procedure is as follows:
1. Before restoring factory data, enable encryption on your device in the Security menu in device settings. This will cause your data to be accessible only with a password set by you. So even if the files are retrieved, it will be difficult to read them.
2. Restore the factory settings. Through the many changes that our dear manufacturers make the devices, the path varies – in pure Android, this option is a menu called “Back up and reset.” Your smartphone will restart and the data already encrypted, will be deleted.
Only the above two steps are enough. If you want to insure, fill your smartphone useless data (songs or videos that you do not mind that others have access, for example) to overwrite the previous data and repeat step 2.