The Periscope is an interactive device supporting passengers in a car to explore the outside environment. Following an experience design process, we trigger positive emotions by addressing psychological needs: (a) The exploration of interesting places around the car addresses the need for stimulation. (b) When passing the Periscope on to others, discoveries can be shared and discussed, creating a feeling of relatedness among the group. We provide insights on the importance of the experience story throughout the design process and details on the interaction concept for the Periscope. Based on the story and a storyboard, we built three hardware prototypes at different early stages of the process, allowing to evaluate whether the story can be experienced during the interaction with the Periscope. Results show that early experience prototypes, implemented with regards to the story, are essential to maintain the designed experience throughout the development. With this case study, we continue the quest of introducing the car as a design space to create meaningful experiences.

Peripheral interaction, like ambient information systems (AIS), aims at leveraging the periphery of our attention. While ambient information systems address the perception of information, peripheral interaction targets lightweight interaction outside of the current focus of attention. A number of prototypes have demonstrated the value of peripheral interaction through long-term in-situ deployments. Such studies are particularly suited to evaluate peripheral interaction since they enable the integration of devices into daily routines and thereby move interaction to the periphery of attention. However, they do not lend themselves well to early design phases. In fact, the design process completely lacks early evaluation tools to assess design choices.

Couples in long-distance relationships (LDR) want to keep in touch, share emotions and feel connected despite the geographical distance. Current approaches to solve this problem include dedicated objects, common communication channels and mobile applications (apps). To combine the advantages of all three approaches, this paper introduces a hybrid approach called cubble. cubble enables partners to share their emotions, simple messages and remote presence. The prototype offers color signals augmented with vibration patterns and thermal feedback. We performed qualitative user explorations, which show that users favor the hybrid communication concept and found that this fostered their intimate communication by providing emotional closeness.

Using digital gadgets we authenticate ourselves regularly. Usually authentication relies on standard PIN or password but novel input hardware facilitates new authentication techniques. In this work we present an authentication mechanism based on body movements captured by a depth sensor. This idea is motivated by the cultural body movements used as welcoming gestures, especially by gang members (secret handshakes). Our authentication technique 'BroAuth' lets the user interact with a virtual partner to perform password input. This is done through touching target zones on the own body and on the body of a virtual partner.

In our everyday life, the perception of thermal cues plays a crucial role for the identification and discrimination of materials. When touching an object, the change of temperature in the skin of our fingertips is characteristic for the touched material and can help to discriminate objects with the same texture or hardness. However, this useful perceptual channel is disregarded for interactive elements on standard touchscreens. In this paper, we present a study in which we compared the rate of object discrimination for stand-alone thermal stimuli as well as supplemental thermal stimuli characterizing virtual materials on a touchscreen. Our results show that five materials could be discriminated at a stable rate using either stand-alone or supplemental thermal stimuli. They suggest that thermal cues can enable material discrimination on touch surfaces, which gives way for expanded use of thermal stimuli on interactive surfaces.

Working with digital devices, we often do not focus on one task but switch back and forth between several tasks. Usually some of these tasks are only small secondary tasks. But in contrast to the analog world, where we can carry out such tasks in the periphery of our attention (e.g., drinking a cup of tea while being engaged in a conversation), digital devices normally force us to switch windows, context and thereby the center of our attention independent from the magnitude of the task. To improve multitasking with small tasks (e.g., setting the IM state) I am taking a closer look at peripheral interaction, interaction that can be carried out in the periphery of our attention. Thereby I want to minimize disruption by secondary tasks, to carry out both types of tasks, primary and peripheral, more efficiently. To achieve that goal I developed a preliminary classification and selected several aspects to investigate in more detail.

Instant messaging systems, such as Skype, offer text, audio and video channels for one-on-one and group conversations, both for personal and professional communication. They are commonly used at a distance, i.e., across countries and continents. To avoid disrupting other tasks, they display personal states to signal others when to contact someone and when not. This mechanism, however, heavily relies on users setting their own state correctly. In an online survey with 46 participants we found that neglecting state updates leads to unwanted messages, either because the state is incorrect or others disrespect it because they assume it to be wrong anyway. We address this situation with the StaTube, a tangible object offering (1) peripheral interaction for setting one's own state and (2) peripheral awareness of selected others' state. In an in-situ evaluation we found first indicators that (1) peripheral interaction fosters more frequent state updates and more accurate state information, and (2) that our participants felt more aware of their contacts' states due to the physical ambient representation.

Internet users are targets for ever-advancing phishing- and other attacks. The risks are, for example, to disclose credit card information or passwords to unauthorized instances. One approach to help users with insecure situations is provided by MoodyBoard, which uses ambient information to highlight potential risks. In this paper, we present findings from an evaluation of this system. Two user studies were conducted in order to find out whether an ambient security tool can protect users during sensitive tasks. We designed a pilot study to find out whether users understand the warnings and a security study to see if it helps to protect users from phishing attacks. Results show that MoodyBoard users behaved significantly more secure.

To counter the increasing number of online threats for users' privacy and security, this paper explores the design of an ambient security indicator, in form of a standard keyboard illuminated in different colors, and equipped with additional buttons and vibration functionality. We present the results of a focus group study, which notably influenced the design, and discuss a prototypical implementation called Moody Board.

Near Field Communication (NFC) is an emerging technology for mobile interaction with everyday objects and associated digital resources. Apart from simple interactions with single tags, NFC has the potential for more elaborate interactions with physical objects that comprise multiple tags and serve as physical user interfaces (UI). This paper investigates the design of mobile and physical UIs for the interaction with multiple NFC-tags. It focuses on three basic interactions that qualify for multi-tag interaction-the navigation between parts of an application, the selection of items and the combination of items. Two user studies compare different configurations of mobile and physical UIs for these interactions in order to evaluate the allocation of application features and UI elements to mobile devices and tagged objects. The results advocate the continuous interaction on the latter, instead of splitting interactions between mobile and physical UIs.