Yes, 蓝牙风扇灯 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.
蓝牙风扇灯 is free.
To get estimated revenue of 蓝牙风扇灯 app and other AppStore insights you can sign up to AppTail Mobile Analytics Platform.