# Sleep When I Sleep vs CerePlay

The clearest difference is review sentiment: CerePlay at 57% against Sleep When I Sleep's 0%. CerePlay also leads on rating (3.8 vs 1.0) and update cadence (every 3 weeks vs every 4 months). Sleep When I Sleep's advantage is iOS requirement (11.1 vs 17.2). On price, ratings volume, ads and in-app purchases there is nothing between them.

Both are free to download. Sleep When I Sleep sells 1 in-app purchase, starting at $5.49 per year and CerePlay sells 34 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

CerePlay holds the better App Store score, 3.8 against 1.0. Both are backed by a comparable volume of ratings — 2 and 4 respectively. Written reviews point the same way: 0% of Sleep When I Sleep's written reviews are positive against 57% of CerePlay's.

Sleep When I Sleep ships an update every 4 months, CerePlay every 3 weeks. The most recent releases landed on October 6, 2026 and October 21, 2026 respectively.

## The numbers

| Metric | Sleep When I Sleep | CerePlay |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [1.0 (2 ratings)](https://appshunter.io/ios/app/sleep-when-i-sleep/id1473060489/reviews) | **[3.8 (4 ratings)](https://appshunter.io/ios/app/cereplay/id1665705245/reviews)** |
| Number of ratings | 2 | **4** |
| Positive reviews | 0.0% of reviews | **57.1% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 3 weeks** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 35 MB | 90 MB |
| Requires iOS | **11.1** | 17.2 |
| Devices | **iPhone, iPod, Apple Watch** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [SWIS APP LTD](https://appshunter.io/developer/1473060488) | [CereProc Ltd](https://appshunter.io/developer/572931755) |

## What reviewers say

### Sleep When I Sleep

[App page](https://appshunter.io/ios/app/sleep-when-i-sleep/id1473060489)

This app alerts you when you're falling asleep while listening to audiobooks or podcasts. It pauses playback to help you easily find your place again. It utilizes Apple Watch health data to detect sleep and offers a reset function for continued use.

**Highlights:** Sleep detection alerts, Automatic audio playback pause, Apple Watch integration, Adjustable sensitivity, Easy start/stop functionality

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 7 Day Free Trial | $5.49 | per year |


### CerePlay

[App page](https://appshunter.io/ios/app/cereplay/id1665705245)

Explore a wide range of text-to-speech voices in various languages and accents. Preview and purchase high-quality, human-like voices to enhance your device's linguistic capabilities for productivity or enjoyment.

**Highlights:** Browse text-to-speech voices, Multiple languages and accents, Preview voices before purchase, Human-like voice quality, Supports iPhone and iPad

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (34)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Caitlin TTS | $0.99 | one-time |
| Carolyn TTS | $0.99 | one-time |
| Giles TTS | $0.99 | one-time |
| Jess TTS | $0.99 | one-time |
| Hannah TTS | $0.99 | one-time |
| Katherine TTS | $0.99 | one-time |
| Isabella TTS | $0.99 | one-time |
| Kirsty TTS | $0.99 | one-time |
| Lauren TTS | $0.99 | one-time |
| Megan TTS | $0.99 | one-time |
| Sarah TTS | $0.99 | one-time |
| William TTS | $0.99 | one-time |
| Stuart TTS | $0.99 | one-time |
| Robot TTS | $0.99 | one-time |
| Sue TTS | $0.99 | one-time |
| Ylva TTS | $0.99 | one-time |
| Yuki TTS | $0.99 | one-time |
| Suzanne TTS | $0.99 | one-time |
| Adam TTS | $0.99 | one-time |
| Ben TTS | $0.99 | one-time |
| Daria TTS | $0.99 | one-time |
| Jack TTS | $0.99 | one-time |
| Mairi TTS | $0.99 | one-time |
| Ghost TTS | $0.99 | one-time |
| Demon TTS | $0.99 | one-time |
| Nicole TTS | $0.99 | one-time |
| Amy TTS | $0.99 | one-time |
| Ana TTS | $0.99 | one-time |
| Andy TTS | $0.99 | one-time |
| Ceitidh TTS | $0.99 | one-time |
| Lily TTS | $0.99 | one-time |
| Jordan TTS | $0.99 | one-time |
| Sam TTS | $0.99 | one-time |
| Nathan TTS | $0.99 | one-time |


## Frequently asked questions

### Is Sleep When I Sleep free?

Sleep When I Sleep is free to download, with in-app purchases available.

### Is CerePlay free?

CerePlay is free to download, with in-app purchases available.

### Which has better reviews, Sleep When I Sleep or CerePlay?

CerePlay is rated higher. Sleep When I Sleep averages 1.0 out of 5 from 2 ratings, while CerePlay averages 3.8 from 4 ratings.

### Do Sleep When I Sleep or CerePlay have ads?

Neither Sleep When I Sleep nor CerePlay shows ads.

### Which is updated more often, Sleep When I Sleep or CerePlay?

Sleep When I Sleep ships an update every 4 months, and CerePlay every 3 weeks. Most recently, Sleep When I Sleep was updated on October 6, 2026 and CerePlay on October 21, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*