We present a systematic literature review of cryptocurrency and blockchain research in Human-Computer Interaction (HCI) published between 2014 and 2021. We aim to provide an overview of the field, consolidate existing knowledge, and chart paths for future research. Our analysis of 99 articles identifies six major themes: (1) the role of trust, (2) understanding motivation, risk, and perception of cryptocurrencies, (3) cryptocurrency wallets, (4) engaging users with blockchain, (5) using blockchain for application-specific use cases, and (6) support tools for blockchain. We discuss the focus of the existing research body and juxtapose it to the changing landscape of emerging blockchain technologies to highlight future research avenues for HCI and interaction design. With this review, we identify key aspects where interaction design is critical for the adoption of blockchain systems. Doing so, we provide a starting point for new scholars and designers and help them position future contributions.

The voluntary carbon market is an important building block in the fight against climate change. However, it is not trivial for consumers to verify whether carbon offset projects deliver what they promise. While technical solutions for measuring their impact are emerging, there is a lack of understanding of how to translate carbon offset data into trustworthy interface designs. With interaction between users and offset projects mainly happening online, it is critical to meet this design challenge. To this end, we designed and evaluated interfaces with varying trust cues for carbon offset projects in a randomized online experiment (n=244). Our results show that content design, particularly financial and forest-related quantitative data presented at the right detail level, increases the perceived trustworthiness, while images have no significant effect. We contribute the first specific guidance for interface designers for carbon offsets and discuss implications for interaction design.

While offering many useful features, novel smart home devices also provide an attack surface to users’ allegedly secure place: their homes. Thus, it is essential to employ effective threat mitigation strategies, such as securely configuring devices. We investigate how users can be motivated to do so. To foster secure actions, we designed two types of nudges based on the Protection Motivation Theory (PMT): one with low and one with high level of detail. As such, our nudges particularly target users’ threat appraisal (including perceived severity and likelihood of threats) and self-efficacy to take action. In a randomized online experiment (N = 210), we simulated a smart home setup procedure. Participants chose significantly more secure configurations when being provided with detailed nudges, and indicated higher perceived threat and coping appraisal (i.e., higher protection motivation) after the experiment. Based on our results, we discuss the design and deployment of nudges for (future) smart home setup procedures. Our work can help to a) increase users’ threat awareness in general, and b) motivate users to take actions such as securely configuring their devices.

Engaging first-time users of mobile apps is challenging. Onboarding task flows are designed to minimize the drop out of users. To this point, there is little scientific insight into how to design these task flows. We explore this question with a specific focus on financial applications, which pose a particularly high hurdle and require significant trust. We address this question by combining two approaches. We first conducted semi-structured interviews (n=16) exploring users’ meaning-making when engaging with new mobile applications in general. We then prototyped and evaluated onboarding task flows (n=16) for two mobile cryptocurrency apps using the minimalist instruction framework. Our results suggest that well-designed onboarding processes can improve the perceived usability of first-time users for feature-rich mobile apps. We discuss how the expectations users voiced during the interview study can be met by applying instructional design principles and reason that the minimalist instruction framework for mobile onboarding insights presents itself as a useful design method for practitioners to develop onboarding processes and also to identify when not to.

Cryptocurrencies have increasingly gained interest in practice and research alike. Current research in the HCI community predominantly focuses on understanding the behavior of existing cryptocurrency users. Little attention has been given to early users and the challenges they encounter. However, understanding how interfaces of cryptocurrency systems support, impede, or even prevent adoption through new users is essential to develop better, more inclusive solutions. To close this gap, we conducted a user study (n=34) exploring challenges first-time cryptocurrency users face. Our analysis reveals that even popular wallets are not designed for novice users’ needs, stopping them when they would be ready to engage with the technology. We identify multiple challenges ranging from general user interface issues to finance and cryptocurrency-specific ones. We argue that these challenges can and should be addressed by the HCI community and present implications for building better cryptocurrency systems for novice users.

In recent years, cryptocurrencies have increasingly gained interest. The underlying technology, Blockchain, shifts the responsibility for securing assets to the end-user and requires them to manage their (private) keys. Little attention has been given to how cryptocurrency users handle the challenges of key management in practice and how they select the tools to do so. To close this gap, we conducted semi-structured interviews (N=10). Our thematic analysis revealed prominent themes surrounding motivation, risk assessment, and coin management tool usage in practice. We found that the choice of tools is driven by how users assess and balance the key risks that can lead to loss: the risk of (1) human error, (2) betrayal, and (3) malicious attacks. We derive a model, explaining how risk assessment and intended usage drive the decision which tools to use. Our work is complemented by discussing design implications for building systems for the crypto economy.