# Eight Sleep vs Onion

The clearest difference is review sentiment: Onion at 100% against Eight Sleep's 29%. Onion also leads on in-app purchases (none vs 2) and rating (5.0 vs 4.8). Eight Sleep's advantage is ratings volume (18K vs 1). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Eight Sleep sells 2 in-app purchases, starting at $18.99 per month. Onion asks for nothing beyond the download.

Onion holds the better App Store score, 5.0 against 4.8. That said, the two scores are not equally well evidenced: Eight Sleep has 18K ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 29% of Eight Sleep's written reviews are positive against 100% of Onion's.

Eight Sleep ships an update every 4 days, Onion every 2 days. The most recent releases landed on November 4, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | Eight Sleep | Onion |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.8 (18K ratings)](https://appshunter.io/ios/app/eight-sleep/id1086913845/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/onion-mood-tracker/id6809275835/reviews)** |
| Number of ratings | **18K** | 1 |
| Positive reviews | 28.7% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 4 days | **Every 2 days** |
| Monetization | Free with in-app purchases | **Free** |
| Size | 259 MB | 8 MB |
| Requires iOS | 18.0 | 18.0 |
| Devices | **iPhone, iPad** | iPhone |
| Age rating | 12+ | 12+ |
| Developer | [Eight Sleep, Inc](https://appshunter.io/developer/1105586839) | [Keep It Beezy LLC](https://appshunter.io/developer/1806232111) |

## What reviewers say

### Eight Sleep

[App page](https://appshunter.io/ios/app/eight-sleep/id1086913845)

This advanced sleep system intelligently adjusts temperature and elevation for personalized comfort. It tracks detailed sleep metrics and provides insights to help you wake up refreshed. The system supports up to two users with individual profiles and learns over time.

**Highlights:** Personalized temperature control, Automatic sleep stage tracking, Heart rate and HRV monitoring, Smart alarm with vibration, Dual user sleep profiles, AI-driven sleep insights

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 8+ Pro (Monthly) | $18.99 | per month |
| 8+ Pro (Annual) | $179.99 | per year |

**What reviewers like**

- 🚀 Amazing sleep quality
- 🌡️ Effective temperature control
- 📊 Detailed sleep tracking
- 🤖 Helpful AI features
- 🏆 Great customer service

**What reviewers complain about**

- 🐛 Buggy app with frequent crashes
- 🔌 Requires constant internet connection
- 🕰️ Alarm and temperature controls not intuitive
- 🔄 Inconsistent sleep data and metrics
- 💰 Expensive with mandatory subscription

**Reported bugs**

- App freezes and loses connection to pod
- Alarms not working or turning off properly
- Temperature settings not saving or resetting
- Sleep data not syncing or displaying accurately
- Frequent app crashes and performance issues

**Requested features**

- Apple Watch app integration
- Offline temperature/alarm controls
- Customizable sleep tracking and insights
- Improved alarm snooze/dismiss functionality
- Nap mode and more sleep schedule flexibility


### Onion

[App page](https://appshunter.io/ios/app/onion-mood-tracker/id6809275835)

This app helps you track your moods and journal your thoughts with simple check-ins and customizable options. It offers visual insights into your emotional patterns and allows for private, device-stored entries with optional iCloud backup.

**Highlights:** Simple mood check-ins, Personal journaling, Mood calendar and charts, Customizable moods and associations, Optional daily reminders, Device-only storage, iCloud backup option, Apple Health integration

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

**In-app purchases:** none


## Frequently asked questions

### Is Eight Sleep free?

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

### Is Onion free?

Onion is free to download, with no in-app purchases.

### Which has better reviews, Eight Sleep or Onion?

Onion is rated higher. Eight Sleep averages 4.8 out of 5 from 18K ratings, while Onion averages 5.0 from 1 ratings.

### Do Eight Sleep or Onion have ads?

Neither Eight Sleep nor Onion shows ads.

### Which is updated more often, Eight Sleep or Onion?

Eight Sleep ships an update every 4 days, and Onion every 2 days. Most recently, Eight Sleep was updated on November 4, 2026 and Onion on October 31, 2026.

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