Use Passkeys (Biometrics) as a PIN

npx expo install expo-local-authentication expo-secure-store

{
  "expo": {
    "plugins": [
      [
        "expo-local-authentication",
        {
          "faceIDPermission": "Allow $(PRODUCT_NAME) to use Face ID to secure your wallet."
        }
      ]
    ]
  }
}

npx expo run:ios
# or
npx expo run:android

import { useCreateWallet } from '@chipi-stack/chipi-expo';
import * as SecureStore from 'expo-secure-store';
import { useAuth } from '@clerk/clerk-expo';

export function CreateWalletScreen() {
  const { getToken, userId } = useAuth();
  const { createWalletAsync, isLoading, error } = useCreateWallet();

  const handleCreateWallet = async () => {
    const token = await getToken();
    if (!token || !userId) return;

    // Face ID / Touch ID prompt is shown automatically
    const result = await createWalletAsync({
      params: {
        usePasskey: true,
        externalUserId: userId,
      },
      bearerToken: token,
    });

    // Persist the wallet (no PIN to store — biometrics handle auth)
    await SecureStore.setItemAsync('wallet', JSON.stringify(result.wallet));
  };

  return (/* your UI */);
}

import { useTransfer, getNativeWalletEncryptKey } from '@chipi-stack/chipi-expo';
import * as SecureStore from 'expo-secure-store';
import { useAuth } from '@clerk/clerk-expo';

export function TransferScreen() {
  const { getToken, userId } = useAuth();
  const { transferAsync, isLoading } = useTransfer();

  const handleTransfer = async () => {
    const token = await getToken();
    if (!token || !userId) return;

    // Triggers Face ID / Touch ID automatically
    const encryptKey = await getNativeWalletEncryptKey(userId);
    if (!encryptKey) throw new Error('No wallet key found. Please re-create your wallet.');

    const storedWallet = await SecureStore.getItemAsync('wallet');
    if (!storedWallet) throw new Error('No wallet found.');

    await transferAsync({
      params: {
        encryptKey,
        wallet: JSON.parse(storedWallet),
        token: 'USDC',
        recipient: '0x...',
        amount: 1.0,
      },
      bearerToken: token,
    });
  };

  return (/* your UI */);
}

await transferAsync({
  params: {
    wallet,
    token: "USDC",
    recipient: "0x...",
    amount: 1,
    usePasskey: true,
    externalUserId: userId,
  },
  bearerToken: token,
});

import { useMigrateWalletToPasskey } from '@chipi-stack/chipi-expo';
import * as SecureStore from 'expo-secure-store';
import { useAuth } from '@clerk/clerk-expo';

export function MigrateScreen({ currentPin }: { currentPin: string }) {
  const { getToken, userId } = useAuth();
  const { migrateWalletToPasskeyAsync, isLoading, error } = useMigrateWalletToPasskey();

  const handleMigrate = async () => {
    const token = await getToken();
    const storedWallet = await SecureStore.getItemAsync('wallet');
    if (!token || !userId || !storedWallet) return;

    // Face ID / Touch ID prompt is shown during migration
    const result = await migrateWalletToPasskeyAsync({
      wallet: JSON.parse(storedWallet),
      oldEncryptKey: currentPin,
      externalUserId: userId,
      bearerToken: token,
    });

    // Replace the stored wallet with the re-encrypted version
    await SecureStore.setItemAsync('wallet', JSON.stringify(result.wallet));
    // currentPin no longer works — biometrics are now required
  };

  return (/* your UI */);
}