Subscriptions feel small each month but add up over the years. Here is the honest math for a white noise & sleep sounds app — plus an option with no recurring payment.
| Monthly price | 1 year | 3 years |
|---|---|---|
| $2.99 / mo | ≈ $36 | ≈ $108 |
| $4.99 / mo | ≈ $60 | ≈ $180 |
| $9.99 / mo | ≈ $120 | ≈ $360 |
Illustrative math only (price × 12 × years). Check the current price of any specific app in the App Store — this page does not claim any particular app charges these amounts.
Sereno — A high-end sound machine for sleep, focus & calm — free to try, unlock once
Sereno is free to download, then offers a one-time lifetime unlock instead of a recurring subscription.
Free to startOne-time unlockNo subscriptionNo adsOffline
Free download · one-time lifetime unlock · no subscription.
Get Sereno on the App Store →If an app constantly streams new content or ships heavy server-side features, a subscription can be fair. For a white noise & sleep sounds tool you mostly use as-is — especially one that works offline — a one-time purchase is usually the cheaper, calmer choice over two or three years.
It depends on the app, but the honest math is simple: monthly price × 12 = one year, and most people keep such apps for 2–3 years. A $4.99/month app is about $60 a year, or roughly $180 over three years. Always check the current price in the App Store.
Yes. Sereno is free to download, with a one-time lifetime unlock for complete access and no recurring charge. Check the current App Store listing before unlocking.
Sometimes — if an app ships constant server-side updates or streams new content, a subscription can make sense. For a tool you mostly use as-is, a one-time purchase is usually cheaper over the years.