  Dark patterns are deceptive and malicious properties of user interfaces that
lead the end-user to do something different from intended or expected. While
now a key topic in critical computing, most work has been conducted in Western
contexts. Japan, with its booming app market, is a relatively uncharted context
that offers culturally- and linguistically-sensitive differences in design
standards, contexts of use, values, and language, all of which could influence
the presence and expression of dark patterns. In this work, we analyzed 200
popular mobile apps in the Japanese market. We found that most apps had dark
patterns, with an average of 3.9 per app. We also identified a new class of
dark pattern: "Linguistic Dead-Ends" in the forms of "Untranslation" and
"Alphabet Soup." We outline the implications for design and research practice,
especially for future cross-cultural research on dark patterns.
