# Open Planetarium vs Sideris

The clearest difference is in-app purchases: Open Planetarium at none against Sideris's 1. Open Planetarium also leads on iOS requirement (13.0 vs 15.0). On price, ads and device support there is nothing between them.

Both are free to download. Sideris sells 1 one-off in-app purchase. Open Planetarium asks for nothing beyond the download.

## The numbers

| Metric | Open Planetarium | Sideris |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | — | Every 2 weeks |
| Size | 26 MB | 137 MB |
| Requires iOS | **13.0** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [CatsAI Agency](https://appshunter.io/developer/6799471013) | [Loris BERT](https://appshunter.io/developer/6809145520) |

## What reviewers say

### Open Planetarium

[App page](https://appshunter.io/ios/app/open-planetarium/id6799616519)

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

**In-app purchases:** none


### Sideris

[App page](https://appshunter.io/ios/app/sideris-sky-map-plate-solver/id6809145518)

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlimited Plate Solving | $9.99 | one-time |


## Frequently asked questions

### Is Open Planetarium free?

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

### Is Sideris free?

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

### Do Open Planetarium or Sideris have ads?

Neither Open Planetarium nor Sideris shows ads.

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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.*