A system for providing to a user of a handheld device at least one of location-based information and time-based information includes a server assembly including (1) a server application and a server data storage medium; (2) activity site information periodically updated in the server data storage medium and pertaining to at least one activity site, the activity site information being correspondingly updated in a device data storage medium of the handheld device using a communication link between the handheld device and the server assembly; and (3) a client application on the handheld device adapted to (a) obtain reference location information identifying a reference location; (b) access the activity site information from the device data storage medium; (c) determine a relationship between the activity site information and the reference location, the relationship being at least one of a geographic relationship and a temporal relationship; (d) select at least a portion of the activity site information based on the relationship; and (e) present the portion to the user with reference to the relationship.