As you may notice some info is shown, but the Camera and other info isn't there. Most likely the exif data isn't standard and that's why is not working 100%. 500px must get the exif data using a more robust parser.
For standar exif data yes. For the case of the image from your Lumia it will take longer, I've checked and the options are php exif library (which we are using) or the exif lib (command line). There are not so many exif parsers because the default one does its jobs nicely.