ReactOrganizer/App.js

import {AppLoading, Font,} from 'expo';
import React, {Text} from "react";
import App from "./Main";

export default class App1 extends React.Component {
    constructor() {
        super();
        this.state = {
            isReady: false
        };
    }

    async componentWillMount() {
        this.setState({isReady: false});
        await Font.loadAsync({
            Roboto: require("native-base/Fonts/Roboto.ttf"),
            Roboto_medium: require("native-base/Fonts/Roboto_medium.ttf")
        });

        this.setState({isReady: true});
    }

    render() {
        if (!this.state.isReady) {
            return <AppLoading/>
        }
        return <App/>;
    }
}