iOS devices have four lock options: simple four-digit, six-digit, complex, and biometric (fingerprint or face) scan. A simple passcode consists of four digits and is the default offered on iOS devices. The screenshot on the left shows an example of a simple passcode. The screenshot in the middle shows a complex passcode. A complex passcode can be a combination of any numbers, letters, and symbols. Most forensic tools can crack a simple passcode but cannot currently crack a complex passcode. At best, complex passcodes can be bypassed if the iOS device can enter DFU mode. The screenshot on the right is the fingerprint scan that was introduced with the iPhone 5s. The face unlock was introduced with the unveiling of the iPhone X. A backup passcode must be set for biometric scan errors and, more importantly, to unlock the biometric data in the secure enclave. Thus, the biometric lock is only as strong as the backup password or PIN. If the fingerprint or face unlock is keeping you out, use dictionary files from similar devices to attempt to obtain the lock bypass.

Currently, a complex passcode is more secure than a simple passcode, face unlock, or fingerprint scan.