Systems, apparatus and methods for determining a location of a mobile device are presented. Often a mobile device requests assistance data from a location server. If the mobile device expects a significant delayed response in receiving the assistance data, the mobile device may determine a seed location or rough location estimate from a server. The mobile device may also request a map to display and/or a data structure for its estimator. The mobile device may preload the estimator with the rough location estimate and/or the data structure. After preloading, the estimator determines a location of the mobile device. Also, the mobile device may show the map to a user via a display.