No abstract

The application of mobile computing is currently altering patterns of our behavior to a greater degree than perhaps any other invention. In combination with the introduction of power efficient wireless communication technologies, such as Bluetooth Low Energy (BLE), designers are today increasingly empowered to shape the way we interact with our physical surroundings and thus build entirely new experiences. However, our evaluations of BLE and its abilities to facilitate mobile location-based experiences in public environments revealed a number of potential problems. Most notably, the position and orientation of the user in combination with various environmental factors, such as crowds of people traversing the space, were found to cause major fluctuations of the received BLE signal strength. These issues are rendering a seamless functioning of any location-based application practically impossible. Instead of achieving seamlessness by eliminating these technical issues, we thus choose to advocate the use of a seamful approach, i.e. to reveal and exploit these problems and turn them into a part of the actual experience. In order to demonstrate the viability of this approach, we designed, implemented and evaluated the Ghost Detector -an educational location-based museum game for children. By presenting a qualitative evaluation of this game and by motivating our design decisions, this paper provides insight into some of the challenges and possible solutions connected to the process of developing location-based BLE-enabled experiences for public cultural spaces.

Mashup tools are a class of integrated development environments that enable rapid, on-the-fly development of mashups-a type of lightweight Web applications mixing content and services provided through the Web. In the past few years there have been growing number of projects, both from academia and industry, aimed at the development of innovative mashup tools. From the software architecture perspective, the massive effort behind the development of these tools creates a large pool of reusable architectural decisions from which the design of future mashup tools can derive considerable benefits. In this paper, focusing on the design of mashup tools, we explore a design space of decisions comprised of design issues and alternatives. The design space knowledge not only is broad enough to explain the variability of existing tools, but also provides a road-map towards the design of next generation mashup tools.

Abstract. Mashup is defined as the practice of lightweight composition, serendipitous reuse, and user-centric development on the Web. In spite of the fact that the development of mashups is rather simple due to the reuse of all the required layers of a Web application (functionality, data, and user interface), it still requires programming experience. This is a significant hurdle for non-programmers (end-users with minimal or no programming experience), who constitute the majority of Web users. To cope with this, an End-User Programming (EUP) tool can be designed to reduce the barriers of mashup development, in a way that even non-programmers will be able to create innovative, feature-rich mashups. In this paper, we give an overview of the existing EUP approaches for mashup development, as well as a list of open research challenges.

Location sensing is a key enabling technology for Ubicomp to support contextual interaction. However, the laboratories where calibrated testing of location technologies is done are very different to the domestic situations where 'context' is a problematic social construct. This study reports measurements of Bluetooth beacons, informed by laboratory studies, but done in diverse domestic settings. The design of these surveys has been motivated by the natural environment implied in the Bluetooth beacon standards relating the technical environment of the beacon to the function of spaces within the home. This research method can be considered as a situated, 'ethnographic' technical response to the study of physical infrastructure that arises through social processes. The results offer insights for the future design of 'seamful' approaches to indoor location sensing, and to the ways that context might be constructed and interpreted in a seamful manner.

End-User Development (EUD) can be exploited on the Web, where users have the opportunity to create niche "Web Mashup" applications as a means to address their long tail of situational needs in different domains of application. In this paper, we describe the design and evaluation of NaturalMash, an innovative EUD system for mashups. NaturalMash provides a high level of expressive power while it is still usable by non-professional users. This clearly distinguishes NaturalMash from existing mashup EUD tools that are either too limited or highly specialized for inexperienced users. The NaturalMash user interface efficiently combines different techniques such as live programming, natural language programming, What You See Is What You Get (WYSIWYG), and Programming by Demonstration (PbD). The design of NaturalMash adopts a formative evaluation approach, and has completed two design and evaluation iterations. The paper reports the results of the last formative evaluation and discusses the implications of the findings. The results are promising and suggest that the proposed system has a short and gentle learning curve and enables even non-professional users to rapidly build useful mashups.

HTML5 is a new technology standard promising to empower browsers to become a suitable platform for developing rich Web applications. Whilst it is still considered an emerging technology, in this paper we attempt to capture and explore its impacts on mashup development. To do so, we start with a mashup case study showcasing new HTML5 features. We then move on to explore those aspects of mashup development that are affected and will possibly be enabled by HTML5 in the near future. These aspects are grouped into two categories: short-term impacts, that can be harnessed by mashup developers, and long-term impacts, that should be considered by service/content providers.

Abstract. The design of mashup tools combines elements from enduser development and software composition in the context of the Web. The challenge for mashup tool designers is to provide end-users with suitable abstractions, programming models and tool support for easily composing mashups out of existing Web services and Web data sources. In this paper we describe the design of a natural mashup composition environment based on the EnglishMash controlled natural language. The environment proactively supports users as they are learning the syntax of the EnglishMash language with features such as auto-completion, immediate feedback, live preview of the mashup execution and component discovery and selection based on natural language descriptions.