A method for providing location data of a mobile device using a web service, comprising: receiving location data associated with a mobile device, the mobile device operable to transmit a wireless signal including corresponding location data; receiving a location request from a client using the web service, the location request comprising information identifying the mobile device and the client, a monitoring request, and at least one criterion, the monitoring request comprising a request to monitor location data as compared to the at least one criterion, the at least one criterion comprising a determination of a location of the mobile device within a specified distance of another mobile device; automatically communicating a response to the location request based on the received location data associated with the mobile device; extracting, by the web service, the received at least one criterion and storing the at least one criterion in a monitoring configuration file; determining, by the web service, whether the monitoring configuration file includes at least one unsatisfied criterion; and if the monitoring configuration file includes at least one unsatisfied criterion: receiving additional location data associated with the mobile device and the another mobile device; based on the received additional location data, determining whether one of the at least one unsatisfied criterion has been satisfied; and automatically communicating an alert to the client in response to the one of the at least one unsatisfied criterion being satisfied. receiving location data associated with a mobile device, the mobile device operable to transmit a wireless signal including corresponding location data; receiving a location request from a client using the web service, the location request comprising information identifying the mobile device and the client, a monitoring request, and at least one criterion, the monitoring request comprising a request to monitor location data as compared to the at least one criterion, the at least one criterion comprising a determination of a location of the mobile device within a specified distance of another mobile device; automatically communicating a response to the location request based on the received location data associated with the mobile device; extracting, by the web service, the received at least one criterion and storing the at least one criterion in a monitoring configuration file; determining, by the web service, whether the monitoring configuration file includes at least one unsatisfied criterion; and if the monitoring configuration file includes at least one unsatisfied criterion: receiving additional location data associated with the mobile device and the another mobile device; based on the received additional location data, determining whether one of the at least one unsatisfied criterion has been satisfied; and automatically communicating an alert to the client in response to the one of the at least one unsatisfied criterion being satisfied. receiving additional location data associated with the mobile device and the another mobile device; based on the received additional location data, determining whether one of the at least one unsatisfied criterion has been satisfied; and automatically communicating an alert to the client in response to the one of the at least one unsatisfied criterion being satisfied.