First off, an interesting company, and a friendly group of fellows...  The company was founded by two Amazon.com developers who wrote rank & rate systems.  Founded in January 2006, based in Seattle, with 35 employees, and backed by an A-series round from the Kleiner Perkins, the company has every intention of building a direct-to-consumer, long-term sustainable business around local advertising revenues supported by a free mobile download and online service for social places discovery and event sharing. 

With roots at Amazon, the company has extended that knowledge to mobile location, and have built a patent-pending passive location reporting system based on aspatial rate & rank reviews.  The technology has two components, 1) a location agent client for Java devices and the iPhone that publishes coordinates and recognizes when a device is geographically idle (if it is stagnant, then the software shuts down, thus preserving battery power), and 2) a server-side machine learning algorithm that reports & rates places visited by users who contribute rate & rank data.  This contributed data then becomes a sort of "differential correction" that reduces inherent error and uncertainty with location determinations.  Very neat technology!