Add 'Loading.js'

Loading.js

+import React from 'react';
+import { View, ActivityIndicator, StyleSheet } from 'react-native';
+
+export default function Loading() {
+  return (
+    <View style={styles.loadingContainer}>
+      <ActivityIndicator size='large' color='#6646ee' />
+    </View>
+  );
+}
+
+const styles = StyleSheet.create({
+  loadingContainer: {
+    flex: 1,
+    alignItems: 'center',
+    justifyContent: 'center'
+  }
+});