Never sell your Android phone because it keeps your data
If you recently sold your smartphone chances are that your texts, emails, pictures and Facebook keys are still there, even if you wiped the memory clean. A new study by computer researchers at the University of Cambridge shows that “factory reset” on Android devices doesn’t erase everything and sometimes it doesn’t even come close. The extraction of data from resold devices is a growing threat as more users buy second-hand devices. A healthy second-hand market is valuable for vendors as people are more willing to buy expensive new devices if they know they can trade them in later.
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 expanding in size until may be 2018. Researchers tested 21 phones made by Google, HTC, LG, Motorola and Samsung. 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. In other circumstance the devices never wiped out the part where most people store their pictures. The devices affected by this include the HTC One, HTC Sensation XE, Motorola Razr I, Samsung Galaxy S, Samsung Galaxy S2, Samsung Galaxy S Plus and others. Researchers said the Google Nexus 4 performed the best but it still had issues.
The tested phones had unique or different problems. For example, the HTC One didn’t wipe its internal SD card where pictures are stored. The blame of all the shortcomings were pointed to Google because it makes the Android software and runs all the phones.
If a person sells a phone there is no way to be sure that all the data is completely wiped out. Deleting texts, photos, mails or any information from the phone manually does not destroy the files completely because the flash memories the phones use are difficult to erase.
The only secured way is by encrypting all the files in the phone but it will be hard to sell it. A cybersecurity expert in Norway Per Thorsheim said that never sell your old phone when you have a secured option of smashing it.
The options Google normally give when a person wants to wipe the memory clean is by hitting factory reset and updating to a new version of Android that allows for encryption with a passcode. However the procedure is not 100% reliable. Google also offers an option to protect your Google-related information and documents like Gmail, Drive documents and maps.