Yes, スピプレ(英語を毎日話そう!) is free to download, however it contains in-app purchases or subscription offerings.
Not enough reviews to make a reliable assessment. The app needs more user feedback.
スピプレ(英語を毎日話そう!) has several in-app purchases/subscriptions, the average in-app price is EGP 199.99.
To get estimated revenue of スピプレ(英語を毎日話そう!) app and other AppStore insights you can sign up to AppTail Mobile Analytics Platform.