# Duux vs Ceryn

The clearest difference is in-app purchases: Duux at none against Ceryn's 2. Ceryn's advantage is update cadence (every 2 days vs monthly). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Ceryn sells 2 in-app purchases, starting at $1.99 per month. Duux asks for nothing beyond the download.

Duux ships an update monthly, Ceryn every 2 days. The most recent releases landed on September 30, 2026 and October 2, 2026 respectively.

## The numbers

| Metric | Duux | Ceryn |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (15 ratings)](https://appshunter.io/ios/app/duux/id1627712939/reviews)** | — |
| Number of ratings | **15** | — |
| Positive reviews | 29.4% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Monthly | **Every 2 days** |
| Monetization | Ad-supported | — |
| Size | 122 MB | 58 MB |
| Requires iOS | **15.1** | 16.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, Apple Watch |
| Age rating | 4+ | 4+ |
| Developer | [Duux B.V.](https://appshunter.io/developer/1474620118) | [Leliveld Holding BV](https://appshunter.io/developer/1896117333) |

## What reviewers say

### Duux

[App page](https://appshunter.io/ios/app/duux/id1627712939)

Control and monitor your smart air treatment devices from anywhere. Schedule operations, adjust settings, and ensure optimal air quality for a healthier living environment. Experience a smarter, more connected home.

**Highlights:** Real-time device monitoring, Easy scheduling of operations, Remote control from anywhere, Intuitive user interface, Manage air treatment devices

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

**In-app purchases:** none

**What reviewers like**

- 🚀 Heater works well and warms room quickly
- 👍 Slick design and intuitive app
- 👍 Excellent user experience
- 🚀 Powerful and effective
- 👍 Recommended product

**What reviewers complain about**

- 🐛 App is buggy and unreliable
- 🐛 Frequent disconnections and connection issues
- 🐛 App is useless, doesn't work as advertised
- 🐛 App is outdated and lacks functionality
- 🐛 App is terrible, freezes device

**Reported bugs**

- App frequently loses connection with device
- App unable to find or add device
- App UI and functionality regressed with updates
- Devices randomly disconnecting from WiFi
- App login/registration issues

**Requested features**

- Add ability to edit schedules
- Implement away mode or low temperature setting
- Allow rearranging of rooms in app
- Add more scheduling options and flexibility
- Improve Alexa/Google Home integration


### Ceryn

[App page](https://appshunter.io/ios/app/ceryn/id6765890505)

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Ceryn Intelligence | $1.99 | per month |
| Ceryn Intelligence | $19.99 | per year |


## Frequently asked questions

### Is Duux free?

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

### Is Ceryn free?

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

### Do Duux or Ceryn have ads?

Neither Duux nor Ceryn shows ads.

### Which is updated more often, Duux or Ceryn?

Duux ships an update monthly, and Ceryn every 2 days. Most recently, Duux was updated on September 30, 2026 and Ceryn on October 2, 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.*