Stytch Consumer SDK/com.stytch.sdk.consumer.biometrics/BiometricsClient/register

register

abstract suspend fun register(parameters: BiometricsParameters): BiometricsRegisterResponse

Registers the device's biometric credential (fingerprint, face, etc.) for the current user. Performs a two-step flow: calls POST /sdk/v1/biometrics/register/start to get a challenge, prompts the user for biometric authentication, then calls POST /sdk/v1/biometrics/register to complete registration. Requires an active session.

Kotlin (Android):

StytchConsumer.biometrics.register(
    BiometricsParameters(
        context = activity,
        sessionDurationMinutes = 30,
    )
)

iOS:

let params = BiometricsParameters(sessionDurationMinutes: 30)
let response = try await StytchConsumer.biometrics.register(params)

React Native:

StytchConsumer.biometrics.register({ sessionDurationMinutes: 30 })

Return

BiometricsRegisterResponse containing the updated session and user.

Parameters

parameters

BiometricsParameters
sessionDurationMinutes — Duration of the session after successful registration, in minutes.
(Android only) context — The FragmentActivity used to display the biometric prompt.
(Android only) allowDeviceCredentials — Whether to allow PIN/pattern/password as a fallback.
(Android only) promptData — Custom title, subtitle, and description for the biometric prompt.
(Android only) allowFallbackToCleartext — Whether to store the key in cleartext if the secure enclave is unavailable.
(iOS only) promptData — Custom reason string shown in the Face ID / Touch ID prompt.

Throws

BiometricsAlreadyEnrolled

if a biometric registration already exists on this device.

NoSessionExists

if no active session is present.

BiometricsUnsupportedError

if the device does not support biometrics.

StytchError

if registration fails.

CancellationException

if the coroutine is cancelled.