Create cryptographic signatures using device biometrics with keys stored in Secure Enclave (iOS/macOS) and StrongBox/Keystore (Android).
Everything you need to implement secure biometric authentication in your Flutter app.
Keys are generated and stored in Secure Enclave (iOS/macOS) and StrongBox/Keystore (Android). Private keys never leave the secure hardware.
Create RSA-2048 or ECDSA (P-256) signatures that your backend can independently verify. True proof of identity.
Decrypt sensitive data using hybrid ECIES encryption with X9.63 key derivation, SHA-256, and AES-GCM.
Seamless integration with FaceID, TouchID, and Android BiometricPrompt. Native UI on every platform.
Optionally invalidate keys when biometric enrollment changes. Detect if fingerprints or Face ID have been modified.
Allow PIN, pattern, or password fallback on Android when biometrics are unavailable.
Native implementation on every platform. No compromises.
From enrollment to verified signature in four steps.
Generate hardware-backed key pair with biometric protection.
Send the public key to your backend for future verification.
User authenticates, hardware signs the payload.
Backend verifies the signature using the stored public key.
Integrate secure biometric signatures in minutes with our well-documented API. Full platform customization when you need it.
// Create biometric-protected keys
final result = await BiometricSignature()
.createKeys(
enforceBiometric: true,
promptMessage: "Authenticate to register",
);
if (result != null) {
// Send public key to your backend
await api.registerPublicKey(result.publicKey);
}// Sign a challenge from your server
final signature = await BiometricSignature()
.createSignature(
options: SignatureOptions(
payload: serverChallenge,
promptMessage: "Confirm transaction",
),
);
// Send signature to backend for verificationGet started in minutes. Check out the documentation and example app.