```jsx
import { View, Button, Text } from 'react-native';
import { Amplify } from 'aws-amplify';
import { Authenticator, useAuthenticator } from '@aws-amplify/ui-react-native';

import awsExports from './src/aws-exports';
Amplify.configure(awsExports);

function Footer() {
  const { toResetPassword } = useAuthenticator();
  return (
    <Button onPress={toResetPassword} title="Custom Reset Password" />
  );
},

export default function App() {
  return (
    <Authenticator components={{
      SignIn: (props) => <Authenticator.SignIn {...props} Footer={Footer} />
    }}>
      <View>
        <Text>Hello {user.username}</Text>
        <Button onPress={signOut} title="Sign out" />
      </View>
    </Authenticator>
  );
}
```