Calm Chen
Good concept. But I think the flow a bit too slow (When your answer is correct, you need to wait for the next question. When your answer is correct, you need press 答え and 次へ. Constantly bringing your finger up and down is tiring.) My suggestion is, remove the 5 seconds countdown before starting each quiz, skip さいてん, 答え and 次へ, and combine the scoring page (?/5 正解した) with もうすこしがんばりましょう into 1 page. Also, I found that the retention rate was not good. I don't remember the vocab after few days.