The brief
Lumen is a speed-reading and focus trainer for people who want to improve reading speed without losing comprehension. The product expanded into multilingual use: someone can use the interface in English, Afrikaans, or Portuguese while training in a different language path. That meant the app could not treat "language" as a single setting. It needed separate app-language and training-language state, per-language progress, reading history, spaced repetition cards, analytics, onboarding, and a native payment model across web, iOS, and Android.
