# Clean Air in Cities vs Whenn

The clearest difference is update cadence: Whenn at every 8 days against Clean Air in Cities's every 3 weeks. Whenn also leads on iOS requirement (15.1 vs 17.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Clean Air in Cities ships an update every 3 weeks, Whenn every 8 days. The most recent releases landed on October 23, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Clean Air in Cities | Whenn |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Every 8 days** |
| Monetization | Free | — |
| Size | 30 MB | 21 MB |
| Requires iOS | 17.0 | **15.1** |
| Devices | **iPhone, iPad, Apple Watch** | iPhone, iPod |
| Age rating | 4+ | 17+ |
| Developer | [Clean Air in London](https://appshunter.io/developer/646281819) | [Whenn Limited](https://appshunter.io/developer/1660258847) |

## What reviewers say

### Clean Air in Cities

[App page](https://appshunter.io/ios/app/clean-air-in-cities/id646281816)

This app provides real-time air quality data, including PM2.5 and ozone levels, and forecasts for your location. It illustrates the health impact of air pollution on populations and offers daily notifications.

**Highlights:** Real-time PM2.5 and ozone concentrations, Daily air pollution forecast notifications, Population health impact assessment, Short-term and long-term exposure alerts, WHO guideline-based alert bands

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

**In-app purchases:** none


### Whenn

[App page](https://appshunter.io/ios/app/whenn/id1660258574)

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

**In-app purchases:** none


## Frequently asked questions

### Is Clean Air in Cities free?

Clean Air in Cities is free to download, with no in-app purchases.

### Is Whenn free?

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

### Do Clean Air in Cities or Whenn have ads?

Neither Clean Air in Cities nor Whenn shows ads.

### Which is updated more often, Clean Air in Cities or Whenn?

Clean Air in Cities ships an update every 3 weeks, and Whenn every 8 days. Most recently, Clean Air in Cities was updated on October 23, 2026 and Whenn on October 25, 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.*