# SinEnvironment vs SG Air Index (PSI)

The clearest difference is ads: SinEnvironment at none against SG Air Index (PSI)'s shown. On price, in-app purchases, device support and iOS requirement there is nothing between them.

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

## The numbers

| Metric | SinEnvironment | SG Air Index (PSI) |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | — | Every 9 days |
| Size | 3 MB | 79 MB |
| Requires iOS | 16.1 | **15.0** |
| Devices | iPhone, iPad | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Hung Dang](https://appshunter.io/developer/1523869579) | [KingRex Solution](https://appshunter.io/developer/1659447067) |

## What reviewers say

### SinEnvironment

[App page](https://appshunter.io/ios/app/sinenvironment/id6505028362)

**In-app purchases:** none


### SG Air Index (PSI)

[App page](https://appshunter.io/ios/app/sg-air-index-psi/id6812280617)

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

**In-app purchases:** none


## Frequently asked questions

### Is SinEnvironment free?

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

### Is SG Air Index (PSI) free?

SG Air Index (PSI) is free to download, with no in-app purchases.

### Do SinEnvironment or SG Air Index (PSI) have ads?

SG Air Index (PSI) shows ads; SinEnvironment does not.

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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.*