A request is received for a service from an application of a mobile computing device. A latitude and a longitude of a geographic location associated with the mobile computing device is determined. The geographic location is mapped to a corresponding location on an embedded map associated with the application, where the embedded map is divided into a plurality of level 1 grids. A level 1 grid is determined in which the corresponding location is located. A granularity corresponding to a geographic distance is determined. The granularity is converted into a corresponding step size on the embedded map. The level 1 grid is divided into a plurality of level 2 grids based on the corresponding step size.