覚える単語帳 is not free (it costs 29000.00), however it doesn't contain in-app purchases or subscriptions.
Not enough reviews to make a reliable assessment. The app needs more user feedback.
The price of 覚える単語帳 is 29000.00.
To get estimated revenue of 覚える単語帳 app and other AppStore insights you can sign up to AppTail Mobile Analytics Platform.