eventCommunication.js

// In some app (say, a flickr-image-app):
appApi.emit('image-selected-for-upload', { url: someUrl, source: 'flickr' })
appApi.on('image-uploaded', function(e) {
    if (e.data.source !== 'flickr') {
        return;
    }
    
    alert('Image uploaded');
});

// In some other app (Imbo, for instance):
appApi.on('image-selected-for-upload', function(e) {
    imbo.addImageFromUrl(e.data.url, function(err, response) {
        if (err) {
            return console.error(err);
        }
        
        appApi.emit('image-uploaded', { source: e.source });
    });
});

// Which also would allow multiple apps to both emit and listen for events in an intuitive manner