# Prime Number Checker vs AirSync Sender

The clearest difference is device support: AirSync Sender at 4 against Prime Number Checker's 2. Prime Number Checker's advantage is iOS requirement (9.0 vs 13.0). On price, update cadence, ads and in-app purchases there is nothing between them.

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

Prime Number Checker ships an update every 5 weeks, AirSync Sender monthly. The most recent releases landed on October 3, 2026 and October 15, 2026 respectively.

## The numbers

| Metric | Prime Number Checker | AirSync Sender |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[1.8 (5 ratings)](https://appshunter.io/ios/app/airsync-sender/id6453759985/reviews)** |
| Number of ratings | — | **5** |
| Positive reviews | — | 50.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 5 weeks | **Monthly** |
| Monetization | — | Free |
| Size | 10 MB | 82 MB |
| Requires iOS | **9.0** | 13.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [Adam Thuvesen](https://appshunter.io/developer/1110341546) | [ViewSonic_International](https://appshunter.io/developer/871648106) |

## What reviewers say

### Prime Number Checker

[App page](https://appshunter.io/ios/app/prime-number-checker/id1114293126)

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

**In-app purchases:** none


### AirSync Sender

[App page](https://appshunter.io/ios/app/airsync-sender/id6453759985)

Wirelessly share your device's screen to compatible interactive displays or multiple iOS devices. Facilitates efficient multi-person communication and collaboration through features like split screen and annotation.

**Highlights:** WebRTC screen sharing, QR code sharing, Split screen support, Moderator mode, Remote control, Annotation, Screen mirroring

**In-app purchases:** none


## Frequently asked questions

### Is Prime Number Checker free?

Prime Number Checker is free to download, with no in-app purchases.

### Is AirSync Sender free?

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

### Do Prime Number Checker or AirSync Sender have ads?

Neither Prime Number Checker nor AirSync Sender shows ads.

### Which is updated more often, Prime Number Checker or AirSync Sender?

Prime Number Checker ships an update every 5 weeks, and AirSync Sender monthly. Most recently, Prime Number Checker was updated on October 3, 2026 and AirSync Sender on October 15, 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.*