I was considering showing the readings in romanized format but came to the conclusion that there is not much point learning kanji if you are not going to bother learn hiragana. Also, although Moekana was developed as a product aimed at foreigners learning Japanese, many Japanese parents bought Moekana for their kids to learn Hiragana and it even became the
2nd best selling anime product on Amazon Japan. Therefore, I've decided to keep the "kun" and "on" readings in hiragana - it caters for domestic folks in Japan and forces you to learn hiragana before you attempt kanji - because there is not much point learning kanji without hiragana!