A free deduction game: read a climate graph (temperature and rainfall) and identify the city and climate zone. Repeatedly 'reading' graph shapes builds the pattern recognition that geography exams reward.
Questions are in Japanese (interface in English). Your detective rank rises as you play, and your deductions get faster and sharper — climate training that fits on your phone.
Answer the same question correctly twice and it graduates into a mastery card; the ranking counts how many cards you have collected. You can drill only the questions you got wrong, and every day you play adds a study stamp. No sign-up is required and your records stay on your own device. (The questions themselves are in Japanese.)