Adrian Holzer

Mobile application market: A developer's perspective

Major software companies, such as Apple and Google, are disturbing the relatively safe and established actors of the mobile application business. These newcomers have caused significant structural changes in the market by imposing and enforcing their own rules for the future of mobile application developments. The implications of these changes do not only concern the mobile network operators and mobile phone manufacturers but also bring additional opportunities and constraints for current mobile application developers. Therefore, developers need to assess what their options are and how they can take advantage of these current trends. In this paper, we take a developers perspective in order to explore how the identified trends will impact the mobile application development markets. Our preliminary analysis leads us to suggest eight propositions which summarize our findings and can be the starting points for future empirical research.

Trends in Mobile Application Development

Major software companies, such as Apple and Google, are disturbing the relatively safe and established actors of the mobile application business. These newcomers have caused significant structural changes by imposing and enforcing their own rules for the future of mobile application development. The implications of these changes do not only concern the mobile network operators and mobile phone manufacturers. This changed environment also brings additional opportunities and constraints for current mobile application developers. Therefore, developers need to assess what their options are and how they can take advantages of these current trends. In this paper, we take a developer’s perspective in order to explore how the structural changes will influence the mobile application development markets. Moreover, we discuss what aspects developers need to take into account in order to position themselves within the current trends.

Towards an Online Lab Portal for Inquiry-Based STEM Learning at School

Nowadays, the knowledge economy is growing rapidly. To sustain future growth, more well educated people in STEM science, technology, engineering and mathematics are needed. In the Go-Lab project we aim to motivate and orient students from an early age on to study STEM fields in their future educational path by applying inquiry learning using online labs. This paper presents an inquiry learning portal where teachers can discover, use and enhance online labs appropriate for their courses and students can acquire scientific methodology skills while doing experiments using the labs. The Go-Lab portal architecture is presented, which contains a repository of online labs, inquiry learning spaces and complementary services. The paper discusses a first version of the portal and our future plans.

Perceiving Learning at a Glance: A Systematic Literature Review of Learning Dashboard Research

This paper presents a systematic literature review of the state-of-the-art of research on learning dashboards in the fields of Learning Analytics and Educational Data Mining. Research on learning dashboards aims to identify what data is meaningful to different stakeholders and how data can be presented to support sense-making processes. Learning dashboards are becoming popular due to the increased use of educational technologies, such as Learning Management Systems (LMS) and Massive Open Online Courses (MOOCs). The initial search of five main academic databases and GScholar resulted in 346 papers out of which 55 papers were included in the final analysis. Our review distinguishes different kinds of research studies as well as various aspects of learning dashboards and their maturity regarding evaluation. As the research field is still relatively young, most studies are exploratory and proof-of-concept. The review concludes by offering a definition for learning dashboards and by outlining open issues and future lines of work in the area of learning dashboards. There is a need for longitudinal research in authentic settings and studies that systematically compare different dashboard designs.

Six-Shot Broadcast: A Context-Aware Algorithm for Efficient Message Diffusion in MANETs

In this paper, we introduce six-shot broadcast (6SB) , a new context-aware message diffusion algorithm that uses location information to fine-tune its broadcasting process. Message diffusion is indeed one of the core challenges brought up by distributed systems and has therefore largely been studied in the context of traditional network structures such as the Internet. With the emergence of mobile ad hoc networks (MANETs) , new broadcasting algorithm especially geared at these networks have been introduced. These algorithms must reach two conflicting objectives when broadcasting a message, namely reliability vs. efficiency. That is, they must maximize the number of nodes that deliver the message (reliability), while minimizing the number of nodes that forward the message (efficiency). In recent years as more and more mobile devices have become context-aware, several broadcasting algorithms have been introduced using contextual information, such as location, in order to increase reliability and efficiency. Along that line, we provide a in-depth performance evaluation of our 6SB algorithm, by comparing it to similar broadcasting algorithms also targeted at MANETs . Our results show that 6SB competes with the most efficient algorithms in high densities of nodes and offers increased reliability in low densities at a reasonable overhead.

Middleware Support for Context-Aware Applications

With computing devices becoming more mobile and pervasive, a stronger interaction between an application and its changing environment opens new horizons in terms of application functionalities. Location-based applications, such as GPS navigation systems, are good examples of how information provided to an application on its surroundings offers new kinds of functionalities. Location is one of many environmental variables that might influence the behavior of an application. The notion of context encompasses these variables in the broad sense.

Context-aware broadcasting approaches in mobile ad hoc networks

The aim of this paper is to compare different context-aware broadcasting approaches in mobile ad hoc networks (MANETs) and to evaluate their respective performances. Message broadcasting is one of the core challenges brought up by distributed systems and has therefore largely been studied in the context of traditional network structures, such as the Internet. With the emergence of MANETs, new broadcasting algorithms especially geared at these networks have been introduced. The goal of these broadcasting algorithms is to ensure that a maximum number of nodes deliver the broadcasted message (reliability), while ensuring that the minimum number of nodes retransmit the broadcasted message (efficiency), in order to save their resources, such as bandwidth or battery. In recent years, as more and more mobile devices have become context-aware, several broadcasting algorithms have been introduced that take advantage of contextual information in order to improve their performance. We distinguish four approaches with respect to context: (1) context-oblivious approaches, (2) network traffic-aware approaches, (3) power-aware approaches, and (4) location-aware approaches. This paper precisely aims at presenting these four different broadcasting approaches and at measuring the performance of algorithms built upon them.

Understanding learning at a glance: an overview of learning dashboard studies

Research on learning dashboards aims to identify what data is meaningful to different stakeholders in education, and how data can be presented to support sense-making processes. This paper summarizes the main outcomes of a systematic literature review on learning dashboards, in the fields of Learning Analytics and Educational Data Mining. The query was run in five main academic databases and enriched with papers coming from GScholar, resulting in 346 papers out of which 55 were included in the final analysis. Our review distinguishes different kinds of research studies as well as different aspects of learning dashboards and their maturity in terms of evaluation. As the research field is still relatively young, many of the studies are exploratory and proof-of-concept. Among the main open issues and future lines of work in the area of learning dashboards, we identify the need for longitudinal research in authentic settings, as well as studies that systematically compare different dashboard design options.

Putting events in context: aspects for event-based distributed programming

Event-based programming is an appealing paradigm for developing pervasive systems since events enable the decoupling of interacting components. Unfortunately, many event-based languages and systems have hardwired notions of physical or logical time and space. This limits their adaptability and target deployment environments, as pervasive systems rely on inherent interaction and interchanging of different protocols and infrastructures. This paper introduces domain-specific aspects for capturing event context, generalizing beyond the classic time and space dimensions associated with events. Through examples, we demonstrate that our context aspects - conspects for short - modularize the design and implementation of event contexts, enabling code reuse, and making programs portable across infrastructures. We illustrate the benefits of conspects by using them to transparently switch protocols in two pervasive software suites implemented in EventJava: (1) a tornado monitoring system deployed on different architectures ranging from desktop x86 to embedded LEON3, and (2) a mobile social networking suite with protocols for different application scenarios.

Pervaho: A specialized middleware for mobile context-aware applications

The concept of context-awareness offers a great potential for the future of mobile applications. In order to be developed in an optimal way, mobile context-aware applications need appropriate middleware services. This paper introduces Pervaho, an integrated middleware aimed specifically at supporting the development and testing of mobile context-aware applications. To illustrate the use of Pervaho, we walk through the development of a concrete mobile application and show how it can be built on top of Pervaho’s location-based publish/subscribe service. We also illustrate how a specialized mobility testing tool significantly simplifies the process of testing proximity-based semantics. We then present the implementation of Pervaho, which is based on a set of communication protocols geared at mesh networks. Finally, we provide a performance analysis of our implementation.