Patent ID: 8560512

Claim:
A method of finding elements that match across a plurality of sets of global positioning system (GPS) data, the method comprising: gathering the plurality of sets of the GPS data with two handheld portable electronic devices while users carry the two handheld portable electronic devices; partitioning a representation of each element of a plurality of sets of the GPS data into a series of segments; repeating a matching process to determine if the users carrying the two handheld portable electronic devices were previously at a common geographical location comprising: exchanging portions of the GPS data between the two handheld portable electronic devices by disclosing one of the segments from each element that is from a selected one of the sets and that is a potential match; removing from the potential matches those elements that do not match the disclosed segment; and rotating which among the sets is the selected set; revealing results of the matching process at the two handheld portable electronic devices.