Threema Work
US alternative: SlackSecure business messaging platform from Switzerland built around privacy, data minimization, and organizational control.
Fully European
Overview
Threema Work is the business product line of Threema, offering secure team messaging and mobile communication management for organizations that want a more privacy-preserving alternative to mainstream workplace chat apps. It is a good Antimaga fit because it is clearly productized, widely positioned for business use, and backed by strong official claims around Swiss operation, privacy, and control. Its value proposition is especially relevant for regulated teams and organizations avoiding US workplace messaging defaults.