import React, { Component } from 'react';
import HTMLViewer from 'react-native-htmlviewer';

export default class MyScreen extends Component {
    render() {
	    return (
		    <HTMLViewer 
			    html={"<p>Olá, mundo!</p>"}
		    />
	    );
    }
}

import React, { Component } from 'react';
import HTMLViewer from 'react-native-htmlviewer';

export default class MyScreen extends Component {
    render() {
	    return (
		    <HTMLViewer 
			    html={"<p>Olá, mundo!</p>"}
			    customProps={{
				    img: {
					    maxWidth: Dimensions.get('window').width - 40
				    }
			    }}
		    />
	    );
    }
}