# Keystone Correction vs 単純な電卓

The clearest difference is ads: 単純な電卓 at none against Keystone Correction's shown. 単純な電卓 also leads on update cadence (fortnightly vs every 2 months) and review sentiment (80% vs 67%). Keystone Correction's advantage is iOS requirement (11.0 vs 15.0). On price, 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.

Keystone Correction ships an update every 2 months, 単純な電卓 fortnightly. The most recent releases landed on October 20, 2026 and October 30, 2026 respectively.

## The numbers

| Metric | Keystone Correction | 単純な電卓 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (5 ratings)](https://appshunter.io/ios/app/keystone-correction-comcam/id1504346555/reviews)** | — |
| Number of ratings | **5** | — |
| Positive reviews | 66.7% of reviews | **80.0% of reviews** |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | Every 2 months | **Fortnightly** |
| Monetization | Ad-supported | — |
| Size | 19 MB | 33 MB |
| Requires iOS | **11.0** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Masayoshi Shibata](https://appshunter.io/developer/1474388626) | [MUNEATSU G.K.](https://appshunter.io/developer/1534902759) |

## What reviewers say

### Keystone Correction

[App page](https://appshunter.io/ios/app/keystone-correction-comcam/id1504346555)

Easily scan and auto-correct documents directly on your device. This secure app keeps your images private by not uploading them online, making it ideal for sensitive business use. All functions are available for free, with no registration or complicated steps required.

**Highlights:** Automatic keystone correction, Secure offline processing, Easy document digitization, Free to use all functions, No user registration, Simple interface

**In-app purchases:** none


### 単純な電卓

[App page](https://appshunter.io/ios/app/id1614220696)

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

**In-app purchases:** none


## Frequently asked questions

### Is Keystone Correction free?

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

### Is 単純な電卓 free?

単純な電卓 is free to download, with no in-app purchases.

### Do Keystone Correction or 単純な電卓 have ads?

Keystone Correction shows ads; 単純な電卓 does not.

### Which is updated more often, Keystone Correction or 単純な電卓?

Keystone Correction ships an update every 2 months, and 単純な電卓 fortnightly. Most recently, Keystone Correction was updated on October 20, 2026 and 単純な電卓 on October 30, 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.*