‹ Device capabilities

Function

getBiometryTypes()

The biometric modalities of the device that can unlock a key, enrolled or not; empty without biometric hardware. Use it to name the feature: "Face ID", "Touch ID" or "biometrics".

Import

import { getBiometryTypes } from '@apexnative/keychain';

Usage

src/auth/biometrics.ts

import { BiometryType, getBiometryTypes } from '@apexnative/keychain';

export async function biometryName(): Promise<string> {
  const types = await getBiometryTypes();
  if (types.length === 1 && types[0] === BiometryType.FaceID) return 'Face ID';
  if (types.length === 1 && types[0] === BiometryType.TouchID) return 'Touch ID';
  return 'biometrics';
}

Signature

function getBiometryTypes(): Promise<BiometryType[]>;

ReturnsPromise<BiometryType[]>PromptNeverPlatformsiOSAndroid

Returns

An array of BiometryType: on iOS one of 'faceID', 'touchID', 'opticID'; on Android any of 'fingerprint', 'face', 'iris'. Empty on a device without biometric hardware that can unlock a key.

Notes

• Enrolled or not. The array says what the hardware is, not whether a face or a finger is enrolled. Whether an item can be protected now is canUseAccessControl's answer.
• Why an array. Android doesn't tell an app which modality BiometricPrompt will offer: a phone with a fingerprint sensor and a face sensor may show either. Name the feature by what the array holds, and say "biometrics" when there are several.
• Android lists only devices with strong biometrics. When the device has Class 3 biometrics, which can unlock a Keystore key, the array has its sensors. Android doesn't say the class of each sensor, so a phone with a Class 3 fingerprint sensor and a Class 2 face unlock lists 'face' too, though only the fingerprint opens the items. A device whose biometrics are all weaker gets an empty array.

See also

BiometryTypeThe values in the array.canUseAccessControlWhether an item can be protected now.How biometrics worksWhat the device can tell you.