Yes, 白噪音-失眠、催眠和助眠工具 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.
白噪音-失眠、催眠和助眠工具 has several in-app purchases/subscriptions, the average in-app price is 21.99 ₺.
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