After a device upgrade, users may look into the various resale or trade-in opportunities for older smartphones. Reselling a device that is no longer in use is one of the best ways to get maximum value, but if the owner does not take proper data erasure precautions, their personal information could be stolen.

A basic factory reset does not always clear data from the device permanently. Residual data may stay on a smartphone even after a reset, for this reason, device owners are encouraged to take extra precautions to erase data before trade-in.
Here are three ways to ensure residual data is disposed of.
- Encryption before factory reset
- Encrypting all of a device’s data before completing a factor reset makes accessing residual data extremely difficult. Android 6.0 and iOS 5 automatically encrypt data, but for older versions of OS, users can visit the device’s settings menu to encrypt the device’s data. After data is encrypted, a factory reset will remove all information from the device, and any residual data will remain encrypted.
- Remote wipe of device
- Both Android and Apple offer remote wipe services for devices, meaning users are able to clear their data from a smartphone without having access to the smartphone. Android users can also do this by accessing the Android Device Manager in the Google Play Store, from there users have the option to completely wipe the phone. Similarly, Apple users are able to wipe their iPhone through the Find My iPhone application on iOS devices. Both of these programs require the device’s respective Google or Apple account to access and erase data.
- Work with a certified device refurbisher
- The most reliable way to ensure residual data is not a threat to the past owner is by partnering with a certified mobile asset manager. A certified MAM ensures all data is properly removed from a device, even after factory rest. When working with a mobile asset manager, users should ensure their data erasure practices are NIST standard to ensure full information privacy.
HOBI International, Inc. is an R2, RIOS, IOS 14001 and WBE certified mobile asset manager. HOBI provides the best practices in mobile device data security and erasure, as well as the best refurbishment and recycling opportunities.