I have open-sourced pub-sub-map, a node.js driven web application that presents a map and lets you subscribe to real-time location markers. As marker positions get updated, the new location is pushed to all web browsers subscribed to them in real-time.

How could this be useful? Coupled with an iOS application I'm writing, you could follow a number of runners in a marathon, or see where all the taco trucks or taxis are. Scraping data from various mass transit systems, you could have a realtime display of where all the trains and busses are. Or you could track a model rocket or stratospheric balloon project to see where it lands. Basically, pub-sub-map can be useful for anything that moves where any number of people want to follow in realtime. It is an expansion of what you can already do right now with http://EyeZo.com.

I use express as a web framework running in node.js with jade templates to render the web frontend. I don't use polling to push location information. Instead, all location updates are pushed to subscribed browsers via socket.io also running in the same node.js application.

Here's a video of pub-sub-map in action.



pub-sub-map is the next-generation engine I am developing for http://eyezo.com. Give it a try and let me know what you think.