Those who sell their mobiles online may be putting their most intimate photos, search histories and even identities at risk by failing to permanently delete their data, security firm Avast has revealed.
Data recovery software the company ran on 20 phones bought from eBay was said to yield more than 40,000 photos, including 1,500 of children, 750 of partially naked women, and 250 of naked men.
Jude McColgan, president of mobile at Avast, said: "Deleting files from your Android phone before selling it or giving it away is not enough.
"You need to overwrite your files, making them irretrievable."
The investigation also unearthed 1,000 Google searches, 750 emails and texts, 250 contacts, four identities, and even one completed loan application.
"Stalkers, enemies, and thieves can abuse personal data to stalk, blackmail and steal people's identities," McColgan added.
"They can use this information to watch people's every move, exploit their strange fetishes, open credit cards in their name, or even continue what they started by further selling their personal information online."