Android Erasure
High Level (3 Times) – DoD 5220.22-M – Overwrite the data with a value, then with the inverse of that value, then with a random value, verifying the write after each step. The first two wipes theoretically pull the magnetic field fully in one direction, then fully in the other, eliminating any residue of the original value. Data is overwritten in 1st pass with 0’s, 2nd pass with 1’s, and the last pass with random segments for data sanitization.
iOS Erasure
The defaulted Erasure for iOS is Secure Cryptographic Erase. The data on the device is encrypted by default, a new AES-256 encrypted file system is added and the old encryption keys are permanently removed during the erasure process. Once the device Secure Erase is completed we can regain the connection to the device and update the Erasure status. This encrypted file system replacement makes the recovering of old data impossible.