Quality improvement in mobile applications should be based on the consideration of several factors, such as users' diversity in spatio-temporal usage, as well as the device's resource usage, including battery life. Although application tuning should consider this practical issue, it is difficult to ensure the success of this process during the development stage due to the lack of information about application usage. This paper proposes a user interaction-based profiling system to overcome the limitations of development-level application debugging. In our system, the analysis of both device behavior and energy consumption is possible with fine-grained process-level application monitoring. By providing fine-grained information, including user interaction, system behavior, and power consumption, our system provides meaningful analysis for application tuning. The proposed method does not require the source code of the application and uses a web-based framework so that users can easily provide their usage data. Our case study with a few popular applications demonstrates that the proposed system is practical and useful for application tuning.

Context-aware service provisioning for mobile phones is challenging because of diverse user contexts and mobile applications. The context recognition process generally reduces the device performance due to the competitive use of limited resources in the mobile phone. While extensive attempts have been made to provide appropriate services based on user context, previous work is limited to supporting diverse user contexts and various services. In this paper, we introduce PION, a framework for personalized service provisioning to manage diverse user contexts and provide appropriate mobile services in daily life. PION comprises the Service Hub and Pioneer. The Service Hub is a service agent server between a smartphone user and a service provider that defines the properties of mobile services. The Pioneer collects cognitive context data, classifies user contexts and their relations, and predicts essential mobile services based on a user's mobility data. We have implemented PION on the Android framework, and our evaluation demonstrates its efficiency in managing diverse user contexts and providing mobile services in real deployments. We believe that the PION framework is a viable context-aware system for smartphone users.

This paper presents the design principles, implementation, and evaluation of the RETOS operating system which is specifically developed for micro sensor nodes. RETOS has four distinct objectives, which are to provide (1) a multithreaded programming interface, (2) system resiliency, (3) kernel extensibility with dynamic reconfiguration, and (4) WSN-oriented network abstraction. RETOS is a multithreaded operating system, hence it provides the commonly used thread model of programming interface to developers. We have used various implementation techniques to optimize the performance and resource usage of multithreading. RETOS also provides software solutions to separate kernel from user applications, and supports their robust execution on MMU-less hardware. The RETOS kernel can be dynamically reconfigured, via loadable kernel framework, so a application-optimized and resource-efficient kernel is constructed. Finally, the networking architecture in RETOS is designed with a layering concept to provide WSN-specific network abstraction. RETOS currently supports Atmel ATmega128, TI MSP430, and Chipcon CC2430 family of microcontrollers. Several real-world WSN applications are developed for RETOS and the overall evaluation of the systems is described in the paper.

This demonstration shows the programming development suite of the RETOS operating system for sensor networks, which provides a robust and multithreaded programming interface to application programmers. We first demonstrate how to build the RETOS kernel on the TI MSP430, Atmel ATmega 128 and Chipcon CC2430 family of microcontrollers. The application or a kernel module is then compiled and disseminated, via wireless channel, to the target motes. The GUI-based RMon network management tool for RETOS is also demonstrated to monitor the networked sensors, and even to control the system's parameters or applications running on them via a remote shell. The system is demonstrated to run on a mixed set of MSP430, ATmega128 and CC2430-based motes. Overall, our demonstration will convince attendees of the programming convenience of developing sensor network applications using RETOS, which is, indeed, a mature and practical system that can be used to develop real-world applications.