main.js with browser definitions for the sound machine

main.js

'use strict';

var app = require('app');
var BrowserWindow = require('browser-window');

var mainWindow = null;

app.on('ready', function() {
    mainWindow = new BrowserWindow({
        frame: false,
        height: 700,
        resizable: false,
        width: 368
    });

    mainWindow.loadUrl('file://' + __dirname + '/app/index.html');
});

This is outdated Electron syntax. For electron prebuilt 0.30.3:

'use strict';

const electron = require('electron');
const app = electron.app;
const BrowserWindow = electron.BrowserWindow;

let mainWindow = null;

app.on('ready', function() {
    mainWindow = new BrowserWindow({
        frame: false,
        height: 700,
        resizable: false,
        width: 368
    });

    mainWindow.loadURL('file://' + __dirname + '/app/index.html');
});