Abstract Voice user interface (VUI) systems, such as Alexa, Siri, and Google Assistant, are popular and widely available. Still, challenges such as privacy and the ability to have a dialog remain. In the latter example, the user expects a human‐like conversation, that is, that the VUI understands the dialog and its context. However, this VUI feature of context‐aware interaction is rather error prone. For this reason, we intend to explore the VUI context of use and its impact on interaction, that is, relevant user experience (UX). We see a demand for context‐dependent UX measurement because analyzing the context of use and UX assessment are both critical human‐centered design (HCD) methods. Therefore, we examine the VUI context of use by asking users about how, where, and for what they use VUIs, as well as their UX and improvement proposals. We interviewed people with disabilities who rely on VUIs and people without disabilities who use VUIs for convenience or fun. We identified VUI context‐of‐use categories and factors and explored their impacts on relevant UX qualities. Our result is a matrix containing these elements; thus, it provides an overview of the contextual UX of our target group's VUI interaction. We intend to develop a VUI context‐of‐use conceptual structure in the future based on this matrix, which is needed to create an automated context‐dependent UX measurement recommendation tool for VUIs. This conceptual structure could also be useful for automated UX testing in the context of VUI.

Voice user interface (VUI) evaluation often focuses on user experience (UX) quality measurement of UX aspects for VUIs. However, it is crucial to differ among these UX aspects concerning their relevance to specific target groups, like different usage contexts, or user characteristics such as age. Therefore, we identified potential age-specific characteristics and determine their nature, if any. We applied the Kano model using an age-segmentation to categorize these 32 UX aspects based on VUI user data (N = 384). Our findings reveal that UX aspects of VUIs are broadly consistent across all age groups, and VUI developers and researchers should consider the important ones. Some age effects are visible and could impact the success of VUIs.

Voice User Interfaces (VUIs) are becoming increasingly available while users raise, e.g., concerns about privacy issues. User Experience (UX) helps in the design and evaluation of VUIs with focus on the user. Knowledge of the relevant UX aspects for VUIs is needed to understand the user’s point of view when developing such systems. Known UX aspects are derived, e.g., from graphical user interfaces or expert-driven research. The user’s opinion on UX aspects for VUIs, however, has thus far been missing. Hence, we conducted a qualitative and quantitative user study to determine which aspects users take into account when evaluating VUIs. We generated a list of 32 UX aspects that intensive users consider for VUIs. These overlap with, but are not limited to, aspects from established literature. For example, while Efficiency and Effectivity are already well known, Simplicity and Politeness are inherent to known VUI UX aspects but are not necessarily focused. Furthermore, Independency and Context-sensitivity are some new UX aspects for VUIs.

Currently, voice assistants (VAs) are trendy and highly available. The VA adoption rate of internet users differs among European countries and also in the global view. Due to speech intelligibility and privacy concerns, using VAs is challenging. Additionally, user experience (UX) assessment methods and VA improvement possibilities are still missing, but are urgently needed to overcome users’ concerns and increase the adoption rate. Therefore, we conducted an intercultural study of technology-based users from Germany and Spain, expecting that higher improvement potential would outweigh concerns about VAs. We investigated VA use in terms of availability versus actual use, usage patterns, concerns, and improvement proposals. Comparing Germany and Spain, our findings show that nearly the same amount of intensive VA use is found in both technology-based user groups. Despite cultural differences, further results show very similar tendencies, e.g., frequency of use, privacy concerns, and demand for VA improvements.