# RedCrab Calculator vs Smart Compass Pro

The clearest difference is price: RedCrab Calculator at Free against Smart Compass Pro's $2.99. RedCrab Calculator also leads on iOS requirement (15.6 vs 17.6). Smart Compass Pro's advantage is in-app purchases (none vs 1) and ads (none vs shown). On device support there is nothing between them.

RedCrab Calculator is free to download; Smart Compass Pro costs $2.99 up front. RedCrab Calculator sells 1 one-off in-app purchase. Smart Compass Pro asks for nothing beyond the download.

## The numbers

| Metric | RedCrab Calculator | Smart Compass Pro |
| --- | --- | --- |
| Price | **Free** | $2.99 |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Fortnightly | — |
| Monetization | Free with in-app purchases | — |
| Size | 5 MB | 21 MB |
| Requires iOS | **15.6** | 17.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [少泽 梁](https://appshunter.io/developer/897112791) | [nakhon phagdeechat](https://appshunter.io/developer/386312256) |

## What reviewers say

### RedCrab Calculator

[App page](https://appshunter.io/ios/app/redcrab-calculator/id947845140)

This powerful scientific calculator offers a modern UI and robust engine for users of all levels. It handles basic arithmetic to complex engineering equations with smart expression parsing and a high-precision display. Enjoy a seamless calculation experience with features like history recall and dark mode.

**Highlights:** Basic & Advanced Calculations, Smart Expression Parsing, Calculation History & Reuse, High-Precision Display, Dark Mode & Modern UI, VIP Ad-Free Experience

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 终身会员 | $1.99 | one-time |


### Smart Compass Pro

[App page](https://appshunter.io/ios/app/smart-compass-pro/id6771642420)

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

**In-app purchases:** none


## Frequently asked questions

### Is RedCrab Calculator free?

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

### Is Smart Compass Pro free?

Smart Compass Pro costs $2.99, with no in-app purchases.

### Do RedCrab Calculator or Smart Compass Pro have ads?

RedCrab Calculator shows ads; Smart Compass Pro does not.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*