User Perceptions of Security and Privacy for Group Chat

Secure messaging tools are an integral part of modern society. To understand users' security and privacy perceptions and requirements for secure group chat, we surveyed 996 respondents in the US and UK. Our results show that group chat presents important security and privacy challenges, some of which are not present in one-to-one chat. For example, users need to be able to manage and monitor group membership, establish trust for new group members, and filter content that they share in different chat contexts. We also find that respondents lack mechanisms for determining which tools are secure and instead rely on non-technical strategies for protecting their privacy-for example, self-filtering and carefully tracking group membership. To better understand how these results relate to existing tools, we conduct cognitive walkthroughs (a form of expert usability review) for five popular group chat tools. Our results demonstrate that while existing tools address some items identified in our surveys, this support is partial and is insufficient in many cases. As such, there is a need for improved group chat tools that better align with user perceptions and requirements. Based on these findings, we provide recommendations on improving the security and usability of secure group chat.