The counter problem
The words you need, at the window you're standing at
Knowing the procedure isn't the hard part. The hard part is the moment someone asks you a question in Japanese and you have thirty seconds to answer.
Every errand carries the phrases for that specific counter — city hall, health insurance, the pension office, the bank — in Japanese, romaji and English. Tap to hear it read aloud, or just turn the screen around and point.
Works offline-first for the things you'll need at a counter, because ward offices have famously terrible signal.