# RedCrab Calculator — Scientific Calculator& History

> Scientific Calculator& History (iPhone/iPad app by 少泽 梁.)

- Source: https://appshunter.io/ios/app/redcrab-calculator/id947845140 (this page in markdown: same URL + `.md`)
- Developer: [少泽 梁](https://appshunter.io/developer/897112791)
- Category: Utilities, Finance
- Price: Free with in-app purchases (on sale, was $1.99)
- Age rating: 4+
- Requires: iOS 15.6 · 4 MB
- Languages: American English, Japanese, Chinese (Simplified, China), Chinese (Traditional, Taiwan)
- Released: 2014-12-28
- Data updated: 2026-08-30
- User reviews in markdown: https://appshunter.io/ios/app/redcrab-calculator/id947845140/reviews.md

## What is RedCrab Calculator?

The RedCrab Calculator is an efficient and powerful tool designed for students, engineers, professionals, and everyday users. Whether you're handling simple daily expenses or complex engineering algebra, it provides a precise and lightning-fast calculation experience. Combining an elegant modern UI with a robust calculation engine, every tap is a seamless experience.

Key Features:

- Basic & Advanced Calculations : Flawlessly supports basic arithmetic alongside advanced scientific functions including trigonometry (sin, cos, tan), logarithms (log, ln), exponents (^), roots (ⁿ√x), and modulo (%).
- Smart Expression Parsing : Supports nested parentheses and long expression inputs. It strictly follows mathematical order of operations, displaying exactly what you calculate to ensure accuracy in complex equations.
- History & Result Reuse : Automatically saves your calculation history. The dedicated "Ans" button allows you to instantly recall your last answer, making multi-step calculations a breeze.
- High-Precision Display : Optimized large number display logic supports showing more significant digits, eliminating the frustration of forced and hard-to-read scientific notation.
- Dark Mode & Modern UI : Native support for Dark Mode to protect your eyes. Carefully tuned button layouts, smooth highlight touch feedback, and dynamic font scaling deliver an ultimate user experience.
- VIP Privileges : Unlock VIP membership to enjoy a pure, ad-free, immersive calculation experience, along with access to exclusive premium features.
Scientific Calculator: Making numbers clearer and calculations smarter.

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

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



## Version history (last 5 releases)

### 5.5 — 2026-05-03

Enhance user experience

### 5.3 — 2026-04-18

feat: Add apps to open screen and optimize launch flow
- Add the minimum display time of startup screen to ensure user experience

### 5.2 — 2026-04-14

Feature: Supports application mandatory persistence of dark and scientific computing modes
feat(ui): Optimize calculator interface visuals and add floating animations
feat(onboarding): Add application guidance process

### 5.1 — 2026-04-07

feature (ui): Add the function of switching between scientific mode and normal mode of the calculator
fix: Fixed scientific calculator mode switching icon and localized language processing logic

### 5.0 — 2026-04-02

- New : Introduced VIP membership feature for a pure, ad-free calculation experience.
- New : Added input history saving, "Ans" result reuse support, and smooth button highlight effects.
- New : Full support for Dark Mode, making night-time usage easier on the eyes.
- Optimized : Refactored the calculator's UI layout, optimizing dynamic font sizing and button visual styles.
- Optimized : Improved large number result displays to show more digits and reduce forced scientific notation.
- Fixed : Resolved issues with negative number displays and calculation errors in specific scenarios.
- Under the Hood : Cleaned up and removed unused redundant resources to improve app performance.

## Apps similar to RedCrab Calculator

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Calculator₊](https://appshunter.io/ios/app/calculator/id398129933) | 4.7 (1,726,794) | Free | Utilities |
| [Calculator⁼](https://appshunter.io/ios/app/calculator/id487127942) | 4.6 (358,262) | Free | Utilities |
| [Calculator #](https://appshunter.io/ios/app/calculator/id458535080) | 4.6 (35,876) | Free | Utilities |
| [Calc Pro - The Top Calculator](https://appshunter.io/ios/app/calc-pro-the-top-calculator/id438580059) | 4.7 (358) | $7.99 | Utilities |
| [Calculator +](https://appshunter.io/ios/app/calculator-plus/id351815470) | 4.6 (10,020) | Free | Utilities |
| [Calculator HD Pro Lite](https://appshunter.io/ios/app/calculator-hd-pro-lite/id571121141) | 4.6 (51,312) | Free | Utilities |

## More apps by 少泽 梁

- [BoCake Master](https://appshunter.io/ios/app/bocake-master/id943882845)
- [Livephoto to GIF & Video](https://appshunter.io/ios/app/livephoto-to-gif-and-video/id949455352)
- [Security Photo](https://appshunter.io/ios/app/security-photo/id1447210330)
- [ScanArmor - Secure Privacy QR](https://appshunter.io/ios/app/scanarmor-secure-privacy-qr/id6743648531)
- [Tear Lunar - Almanac FlipClock](https://appshunter.io/ios/app/tear-lunar-almanac-flipclock/id6760871632)

All apps by 少泽 梁: https://appshunter.io/developer/897112791

---

*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-30.*