Better Together: Collaborative Monitoring for Location-based Services

Mobile applications increasingly rely on frequent and accurate position updates-e.g., with GPS- or Wi-Fi-assisted localization techniques-to provide for functionality to their users. The service quality and acceptance of the application depend strongly on the localization accuracy and the introduced costs, in form of the resource consumption, of the used localization technique. Current mechanisms for location retrieval, however, are limited to non-mobile scenarios or still introduce high costs while obtaining the location. In this work, we propose a collaborative location retrieval service for location-based services in mobile scenarios that combines the location information of a subset of users with the connectivity information between users to enable accurate and cost-efficient location estimations. We evaluate a prototype of our solution to study the impact of service compositions in changing environments and to assess the potential of our proposed service compared to the current state-of-the-art used within location-based services. Our results reveal that, depending on the localization technique, the costs can be reduced significantly while the achieved sensing accuracy and fairness among users improves strongly at the same time.