The increasing popularity of GPS device has boosted many applications where more and more GPS logs have been accumulating continuously. Managing and understanding the collected GPS data are two important issues for these applications. On one hand, by indexing the increasing GPS data, we can provide effective retrieval method for users to find the corresponding GPS data interests them. On the other hand, by understanding user’s GPS data, we are more likely to enable novel services which would stimulate people’s passion on contributing GPS data in turn. However, so far, GPS data are still used directly without much understanding. In our project, referred to as GeoLife, we focus on visualization, organization, fast retrieval, and effective understanding of GPS track logs for both personal and public use. It not only provides a powerful platform for people to effectively manage their GPS data but also help them well understand a person’s past experience from GPS data.