GeoGraffiti is a new take on leaving landmarks or notes in selected locations. Instead of just leaving text messages, you get to assign voice notes to locations of particular interest. If you’re in the vicinity of a voice-tagged location, you will then be alerted so you can listen to it. Since it makes use of GPS, this nifty little app will only work on the iPhone. If not for anything else, it’s a novel way of discovering the world by listening to other people’s opinions, and a way for you to also share your views with others as well.

It’s free to download, but just be wary that since the service is completely free of charge, it’s open to abuse as well. Nevertheless, those who know how to utilize this technology responsibly will surely find it a very useful app in the long run.

PS: The video was made before the actual 3G iPhone was released.