Secure Enclave and Hardware-Backed Keys

The Secure Enclave on iOS, and the hardware-backed keystore on Android, is a separate protected area of the device that holds cryptographic keys. Keys created there can be used by the app but never read out, even if the rest of the device is compromised.

Storing keys in hardware is the strongest option a mobile app has. Testing checks whether sensitive keys actually use hardware-backed storage or sit in software where they are easier to extract.