curl works but not browser

I created a simple nodejs app on the Digital Ocean server following the instructions from Digital Ocean. The code is

#!/usr/bin/env nodejs
var http = require('http');
http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('Hello World\n');
}).listen(8080, '138.68.244.XXX');   //138.68.244.XXX is the IP of my Digital Ocean server
console.log('Server running at http://localhost:8080/');

After I started the app by the command “node hello.js” I got output --> “Server running at http://localhost:8080/”

I was able to curl the URL->curl http://138.68.244.XXX:8080 to get “Hello World” on the server itself. However, when I tried http://138.68.244.XXX:8080 on a browser, I got “ERR_CONNECTION_TIMED_OUT” error.

Please help.

Thank you!