BlockChalk Is Location-Based Sidewalk Chalk For Your Mobile Device

With its new geolocation API , Twitter has the potential to delve into the realm of messages that are relevant based on location. But right now, most geotagged tweets are simply regular tweets that are being tagged with location, and really don't have much specifically to do with it. Enter BlockChalk , a new service built around the idea of leaving simple messages directly tied to a specific location. The service, created by Stephen Hood, the former product team lead for Delicious, and Dave Baggeroer of Stanford's Institute of Design, works because they keep it simple . You load up the application on your mobile device, it locates you, and you leave a message. This can be whatever you want: A note about a good cafe, a tip of something in the neighborhood to watch out for, a request to borrow something that someone else may have in the neighborhood, etc. When other people also using the app come upon the area that you've pinned your "Chalk" (their word for message) to, they'll see it on their screen in a stream of Chalks.