Yes, 诗词荟 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.
诗词荟 has several in-app purchases/subscriptions, the average in-app price is USD 2.32.
To get estimated revenue of 诗词荟 app and other AppStore insights you can sign up to AppTail Mobile Analytics Platform.