# Skymonitor vs SumKey

The clearest difference is price: Skymonitor at Free against SumKey's $1.99. Skymonitor also leads on iOS requirement (13.0 vs 16.0). SumKey's advantage is update cadence (every 9 days vs monthly). On ads, in-app purchases and device support there is nothing between them.

Skymonitor is free to download; SumKey costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Skymonitor ships an update monthly, SumKey every 9 days. The most recent releases landed on October 25, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Skymonitor | SumKey |
| --- | --- | --- |
| Price | **Free** | $1.99 |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Monthly | **Every 9 days** |
| Size | 22 MB | 2 MB |
| Requires iOS | **13.0** | 16.0 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Hornche Corporation](https://appshunter.io/developer/1470581522) | [Che Wei Li](https://appshunter.io/developer/6793052965) |

## What reviewers say

### Skymonitor

[App page](https://appshunter.io/ios/app/skymonitor/id1470581523)

**In-app purchases:** none


### SumKey

[App page](https://appshunter.io/ios/app/sumkey-calculator-keyboard/id6793052963)

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

**In-app purchases:** none


## Frequently asked questions

### Is Skymonitor free?

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

### Is SumKey free?

SumKey costs $1.99, with no in-app purchases.

### Do Skymonitor or SumKey have ads?

Neither Skymonitor nor SumKey shows ads.

### Which is updated more often, Skymonitor or SumKey?

Skymonitor ships an update monthly, and SumKey every 9 days. Most recently, Skymonitor was updated on October 25, 2026 and SumKey on October 24, 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.*