The City of Mandeville Website has an interesting tour guide to some of the many historic locations in the community. It's a computer-assisted walking tour that uses what are called "QR codes" to provide information through your cell phone while you are standing in front of a particular landmark.
Here is the map showing the various points of interest that have the QR codes printed on small metal stands in front of each site. To activate the map, CLICK ON THIS LINK, and then follow the directions on that page. Play the video at the bottom of the other page to hear specific QR Code and phone instructions.