Patent ID: 7970415

Claim:
A position engine for determining a location of a mobile device, comprising: a cached location database, said cached location database containing information regarding a cached location of said mobile device, said cached location having been previously determined by said position engine; and a processor operatively connected to said cached location database for receiving and processing a query for a present location of said mobile device, said query for said present location having a granularity associated therewith, said granularity representing a size of a geographic area associated with said present location of said mobile device; said granularity having a granularity variable associated therewith, said granularity variable representing a time required to leave the geographic area associated with said granularity; said position engine being configured to use said granularity variable to adjust a time of said query for said present location of said mobile device to determine whether a time during which said cached location can be returned in response to said query has expired; wherein said position engine is configured to determine, before adjusting said time of said query using said granularity variable, whether said cached location of said mobile device is a special location from which the mobile device will either likely not be moving for a long period of time or will likely be moving a great distance between subsequent queries of actual location.