Dynamic framework for building highly-localized mobile web DTN applications

Proximity-based mobile applications are increasing in popularity. Such apps engage users while in proximity of places of interest (malls, bus stops, restaurants, theatres), but remain closed or unused after the user goes away. Since the number of ‘places of interest’ is constantly growing and can be large, it is impractical to install a large number of corresponding native applications on the phone when each app engages the user for only a small period of time.In this paper, we propose a dynamic framework for deploying highly-localized mobile web applications. Such web applications are deployed locally to users in proximity, and can be opened in the browser. Communication in the web app is performed over the Delay-Tolerant Network of mobile users, removing the need of an Internet connection. DTN protocols can be dynamically added or removed at run-time, allowing each application to use a protocol best suited to its needs. After usage, the web application is closed either manually by the user, or automatically when the user goes away from the place of interest.To restrict deployment of web apps to only those users in a relevant context (e.g.: people walking nearby a store), and to automatically switch off DTN protocols when user context changes, we have extended the framework to be ‘context-aware’, using the low-power barometer sensor on the phone to detect when the user is idle, walking, or in vehicle. Applications can specify which protocols to run in these user contexts, and when to switch them off, reducing power consumption.We have implemented the framework on Android. Our analysis of the framework show that the memory and performance overhead incurred is small. Using this framework, we have written a simple DTN web application for bus-stops to help the physically challenged. Using real-device measurements, we show that adding context awareness to the framework can reduce power consumption by at least 53%.