A new study by computer researchers at the University of Cambridge shows that “factory reset” — at least on Android devices — doesn’t actually erase everything.
Sometimes it doesn’t even come close.
The used smartphone market is huge and about 630 million phones out there are susceptible to this problem, according to the study. Wall Street analysts expect the market will keep blowing up in size until at least 2018.
Researchers tested 21 phones made by Google (GOOGL, Tech30), HTC, LG, Motorola (MSI) and Samsung (SSNLF). In every case, they were able to recover text messages, Google account credentials and conversations on messaging apps. A few emails remained on the device 80% of the time.