Yes, Katakana practice book is completely free and it doesn't have any in-app purchases or subscriptions.
Not enough reviews to make a reliable assessment. The app needs more user feedback.
Katakana practice book is free.
To get estimated revenue of Katakana practice book app and other AppStore insights you can sign up to AppTail Mobile Analytics Platform.
I downloaded this app to practice my katakana and their stroke orders. This is perfect! It's really simple to use. Each katakana has a pronunciation that automatically plays (though the voice is robotic and occasionally hard to understand) and the stroke order is clearly labeled. You can also save pictures of the kana! I really enjoy using this app!
