import { isSupported, authenticate, TouchIDError } from 'react-native-touch-id'; isSupported().then((isOk: boolean) => {}).catch((error: TouchIDError) => {}); authenticate('reason').then((isOk: boolean) => {}).catch((error: TouchIDError) => {}); authenticate('reason', { title: 'Authentication Required', color: '#1306ff', fallbackTitle: 'Fallback Authentication Method' }).then((isOk: boolean) => {}).catch((error: TouchIDError) => {});