# CalculatorRed vs calculator DUO

The clearest difference is in-app purchases: CalculatorRed at none against calculator DUO's 1. CalculatorRed also leads on ads (none vs shown). calculator DUO's advantage is update cadence (every 10 days vs every 4 weeks). On price, device support and iOS requirement there is nothing between them.

Both are free to download. calculator DUO sells 1 one-off in-app purchase. CalculatorRed asks for nothing beyond the download.

CalculatorRed ships an update every 4 weeks, calculator DUO every 10 days. The most recent releases landed on October 27, 2026 and October 9, 2026 respectively.

## The numbers

| Metric | CalculatorRed | calculator DUO |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (3 ratings)](https://appshunter.io/ios/app/calculator-duo/id6739860116/reviews)** |
| Number of ratings | — | **3** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 4 weeks | **Every 10 days** |
| Monetization | — | Free with in-app purchases |
| Size | 1 MB | 11 MB |
| Requires iOS | 17.0 | **16.5** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Kodwerk Software Ltd.](https://appshunter.io/developer/1741040469) | [Wenbin lei](https://appshunter.io/developer/1787331500) |

## What reviewers say

### CalculatorRed

[App page](https://appshunter.io/ios/app/calculatorred/id6496602010)

**Features:** macOS Compatibility

**In-app purchases:** none


### calculator DUO

[App page](https://appshunter.io/ios/app/calculator-duo/id6739860116)

This utility app offers a modern calculator with a visual history feature, eliminating the need to memorize previous calculations. It also includes a comprehensive unit converter and a tip calculator that bases tips on pre-tax amounts.

**Highlights:** Visual history calculator (RESULT SHELF™), Unit converter, Tip calculator (pre-tax), Distraction-free design, Precise and efficient

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $7.99 | one-time |


## Frequently asked questions

### Is CalculatorRed free?

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

### Is calculator DUO free?

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

### Do CalculatorRed or calculator DUO have ads?

calculator DUO shows ads; CalculatorRed does not.

### Which is updated more often, CalculatorRed or calculator DUO?

CalculatorRed ships an update every 4 weeks, and calculator DUO every 10 days. Most recently, CalculatorRed was updated on October 27, 2026 and calculator DUO on October 9, 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.*